#help-0 | Mathematics | Page 703

alpine sable Jul 11, 2021, 1:25 PM

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But like, why can we treat this as a new journey?

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it's like a trick to see it easier, as we know the velocity at B is 4.43, it'd be the same situation as one ball being thrown vertically (at that height h(0)) with an initial velocity of that 4.43

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does this make sense?

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https://www.desmos.com/calculator/jj04hdcbxj

Desmos

Desmos | Graphing Calculator

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How interesting, never knew about this

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It does make sense

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Thank you

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yeah we perfectly can.

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you're welcome.

distant epoch Jul 11, 2021, 1:29 PM

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hi, how do i get the cartesian equation in terms of y from these parametric equations?
x(t) = t^2 - 2; y(t) = t + 1

alpine sable Jul 11, 2021, 1:34 PM

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distant epoch hi, how do i get the cartesian equation in terms of `y` from these parametric eq...

x = t^2 - 2, y = t + 1, so y - 1 = t, and just substitute

distant epoch Jul 11, 2021, 1:35 PM

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alpine sable x = t^2 - 2, y = t + 1, so y - 1 = t, and just substitute

how do i get an equation in terms of y?

alpine sable Jul 11, 2021, 1:35 PM

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Have you tried substituting?

distant epoch Jul 11, 2021, 1:35 PM

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yes

alpine sable Jul 11, 2021, 1:35 PM

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Show me

distant epoch Jul 11, 2021, 1:36 PM

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x + 2 = t^2; t = sqrt(x + 2); y = sqrt(x + 2) + 1

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but which one do i choose?

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the plus minus thing from the square root

alpine sable Jul 11, 2021, 1:37 PM

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Yeah, so you can't

distant epoch Jul 11, 2021, 1:38 PM

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like both of these are valid, no? y = 1 + √ x + 2; y = 1 - √ x + 2

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nvm, only one is valid, but how would i know which one?

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'cause in different set of equations, there's no telling which one is valid, it can be the positive or the negative equation

brisk ferry Jul 11, 2021, 1:44 PM

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How do I isolate tan(x)? is it even possible?

vague coral Jul 11, 2021, 1:44 PM

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solve it as a quadratic equation

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let u = tan x

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you will have u^2 - 4u +1 = 0

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and apply quadratic formula

brisk ferry Jul 11, 2021, 1:47 PM

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Oh ok thanks!

oblique schooner Jul 11, 2021, 1:48 PM

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start to find number of 3-digit numbers without restriction

noble sinew Jul 11, 2021, 1:58 PM

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if the number must end in something specific start with placing that number

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then you can calculate ways to arrange the other positions normally

shrewd otter Jul 11, 2021, 2:38 PM

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You have 8 digits to choose from. Since the number cannot start with 0, you cannot repeat digits and no other restrictions apply, you have 7 choices. Once you made a choice, you now have one fewer digit to choose from (since you already used it), but you can not use the 0, so you again have 7 choices. Finally, for the 3rd digit you have 6 choices.

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7 * 7 * 6 is the number of ways you can arrange the digits.

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If the number must end in zero, then you have 7 * 6 * 1 options.

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Because you have 7 digits besides the 0 to use, but then you used one, so you have 6, and then your 3rd choice is forced.

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If it must end in 2, 4 or 6, then you can do it backwards.

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Alright. Cheers.

alpine sable Jul 11, 2021, 2:41 PM

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A woman fell 144 ft from the top of a building, landing on the top of a metal ventilator box, which she crushed to a depth of 18 in. She survived without serious injury. What acceleration (assumed uniform) did she experience during the collision? Express your answer in terms of g.

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How do we account for changes in her velocity as she lands on top of the ventilator box?

shrewd otter Jul 11, 2021, 2:43 PM

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alpine sable How do we account for changes in her velocity as she lands on top of the ventila...

Newton's third law.

alpine sable Jul 11, 2021, 2:44 PM

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shrewd otter Newton's third law.

Didn't learn it yet

shrewd otter Jul 11, 2021, 2:44 PM

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If you punch a wall, you act with some force F on it with your fist.

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However, the wall acts with a force of -F onto your fist.

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That's why it hurts to punch a wall.

alpine sable Jul 11, 2021, 2:45 PM

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So how does that help me with my velocity question sorry?

shrewd otter Jul 11, 2021, 2:45 PM

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The question states she crushed the box to a depth of 18".

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Meaning she acted with some force F on it.

alpine sable Jul 11, 2021, 2:45 PM

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We didn't learn about forces yet, but continue I guess

shrewd otter Jul 11, 2021, 2:45 PM

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At the same time, the box acted with a force -F onto her.

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Which reduced her velocity.

alpine sable Jul 11, 2021, 2:46 PM

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Right, so don't we have to account for that? Also, we don't know how tall the box is

shrewd otter Jul 11, 2021, 2:46 PM

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The question at first seems like too vague to be answerable.

alpine sable Jul 11, 2021, 2:46 PM

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No, it definitely has an answer

shrewd otter Jul 11, 2021, 2:46 PM

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It does have one, you just cannot deduce it from the given information.

alpine sable Jul 11, 2021, 2:47 PM

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Yes you can

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Otherwise, they wouldn't have asked it

shrewd otter Jul 11, 2021, 2:47 PM

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That's not true. You can be asked a question with no deducible answer.

alpine sable Jul 11, 2021, 2:47 PM

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That's wrong, it has a numerical answer in the answers page of the book

shrewd otter Jul 11, 2021, 2:48 PM

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The acceleration she experienced must depend on the material qualities of the box, which were not given.

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Simply put, it depends on how hard the box was.

alpine sable Jul 11, 2021, 2:49 PM

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Okay, so what can I do?

shrewd otter Jul 11, 2021, 2:49 PM

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Could you look at the answer on the back?

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That might suggest how they wanted to solve it.

alpine sable Jul 11, 2021, 2:49 PM

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Yeah, I got the answer and I arrived at it myself as well.

shrewd otter Jul 11, 2021, 2:49 PM

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What is it?

alpine sable Jul 11, 2021, 2:49 PM

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-96g

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Or, -96 * 9.8

shrewd otter Jul 11, 2021, 2:49 PM

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And how did you arrive at that answer?

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Wait, I'm actually stupid.

alpine sable Jul 11, 2021, 2:50 PM

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Calculated velocity at the end of the 144 ft drop, then calculated velocity at the 18 inches

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Used that to arrive at the acceleration

shrewd otter Jul 11, 2021, 2:50 PM

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Yeah, I believe that's correct.

alpine sable Jul 11, 2021, 2:50 PM

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Why?

shrewd otter Jul 11, 2021, 2:50 PM

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Well, she accelerated with 1g for 144 feet.

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And then retarded with x * g for 18".

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Because the retardation took a much smaller distance, it follows that the force was proportionately greater.

alpine sable Jul 11, 2021, 2:52 PM

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But why would we calculate it like this, her velocity is not the same as I calculated

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Because once she hits the box, it decreases

shrewd otter Jul 11, 2021, 2:52 PM

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Yes, and you're looking for the amount by which it increases.

alpine sable Jul 11, 2021, 2:52 PM

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What?

shrewd otter Jul 11, 2021, 2:52 PM

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Do you say that her acceleration also changes when she hits the box?

shrewd otter Jul 11, 2021, 2:53 PM

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alpine sable What?

Acceleration is the change is velocity.

alpine sable Jul 11, 2021, 2:53 PM

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It has to change, because her velocity changes

shrewd otter Jul 11, 2021, 2:53 PM

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alpine sable It has to change, because her velocity changes

Right, but there's a very key piece of data in the question.

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What acceleration (assumed uniform)

alpine sable Jul 11, 2021, 2:53 PM

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Right, so her acceleration from the impact until 18 inches is constant

shrewd otter Jul 11, 2021, 2:54 PM

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Yes.

alpine sable Jul 11, 2021, 2:54 PM

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I think it clicked

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So her velocity didn't change

shrewd otter Jul 11, 2021, 2:54 PM

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It did.

alpine sable Jul 11, 2021, 2:54 PM

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From the moment of impact

shrewd otter Jul 11, 2021, 2:54 PM

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Just her acceleration didn't.

alpine sable Jul 11, 2021, 2:54 PM

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Oh, wait.

shrewd otter Jul 11, 2021, 2:54 PM

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If her velocity hadn't changed, she would still be accelerating at 1g.

alpine sable Jul 11, 2021, 2:54 PM

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Yes...

shrewd otter Jul 11, 2021, 2:54 PM

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And going through the ground.

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You just assume a perfect world with perfect elastic collision.

alpine sable Jul 11, 2021, 2:55 PM

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Okay, so why is calculating her velocity at the end of 144 ft correct?

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Because she doesn't even go 144 ft

shrewd otter Jul 11, 2021, 2:55 PM

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She accelerates for 144 feet.

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And then she begins retarding.

alpine sable Jul 11, 2021, 2:55 PM

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No she doesn't?

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144 ft is the whole drop

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That includes the ventilator box

shrewd otter Jul 11, 2021, 2:55 PM

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I don't think it does.

alpine sable Jul 11, 2021, 2:55 PM

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Oh no nevermind

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I misread it...

shrewd otter Jul 11, 2021, 2:56 PM

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144 ft is the point the box started exerting force onto her.

alpine sable Jul 11, 2021, 2:56 PM

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So the layout is like this: 144 ft (drop) + height of ventilator box = height of building

shrewd otter Jul 11, 2021, 2:56 PM

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You don't really care about the height of the street.

alpine sable Jul 11, 2021, 2:56 PM

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My bad, I misunderstood and so my drawing was misleading me as well

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Building not street, lol

shrewd otter Jul 11, 2021, 2:56 PM

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You know that she was in free fall for 144 feet.

alpine sable Jul 11, 2021, 2:56 PM

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Yeah, never mind

shrewd otter Jul 11, 2021, 2:56 PM

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And then her acceleration changed.

alpine sable Jul 11, 2021, 2:56 PM

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Now my calculations make a lot more sense

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We find her velocity right before she hits the ventilator box

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And then

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Well, I want to say we want to find as she goes down to 18 inches

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But she could've gone more than 18 inches

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This depends on how big the ventilator box is

shrewd otter Jul 11, 2021, 2:58 PM

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You then ask yourself: "How much would she have to retard to stop after 18 inches?"

alpine sable Jul 11, 2021, 2:58 PM

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But she doesn't stop after 18 inches

shrewd otter Jul 11, 2021, 2:58 PM

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Or how much force would be needed to stop her in 18".

alpine sable Jul 11, 2021, 2:58 PM

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She stops after x inches?

shrewd otter Jul 11, 2021, 2:58 PM

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She does.

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The question says she crushed it to a depth of 18 inches.-

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That is, left an 18 inch deep hole in it.

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That means that she went from full speed to 0 in 18 inches.

alpine sable Jul 11, 2021, 2:59 PM

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Am I misreading it?

shrewd otter Jul 11, 2021, 2:59 PM

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I think so.

alpine sable Jul 11, 2021, 2:59 PM

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The way I thought it is written means that

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The box is x inches tall

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And then when she is done falling on it, it is now 18 inches tall

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Not that the box is now x - 18 inches tall

shrewd otter Jul 11, 2021, 2:59 PM

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If it was that way, the question would not be solvable.

alpine sable Jul 11, 2021, 2:59 PM

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Yeah, okay

shrewd otter Jul 11, 2021, 2:59 PM

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You wouldn't be able to find x.

alpine sable Jul 11, 2021, 2:59 PM

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I know

shrewd otter Jul 11, 2021, 2:59 PM

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But you're right to point out that the scenario doesn't make much sense in the real world. It's an approximation.

alpine sable Jul 11, 2021, 3:00 PM

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It clicked though, it all makes sense now, thanks for your patience

shrewd otter Jul 11, 2021, 3:00 PM

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Cheers.

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Question solved.

timid dome Jul 11, 2021, 3:09 PM

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can two 2d planes be on top of each other?
like this:

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shrewd otter Jul 11, 2021, 3:12 PM

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timid dome

Why not?

timid dome Jul 11, 2021, 3:13 PM

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if so why can two planes contain the same three non collinear points?

shrewd otter Jul 11, 2021, 3:13 PM

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I don't understand.

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If one plane can contain three non colinear points, then certainly two can.

timid dome Jul 11, 2021, 3:15 PM

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?

shrewd otter Jul 11, 2021, 3:16 PM

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timid dome ?

Ah, I see what you mean.

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In this case, you can say that the two planes are the same.

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Since they contain the same set of points.

timid dome Jul 11, 2021, 3:17 PM

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oh, i see

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ty

noble stone Jul 11, 2021, 3:28 PM

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qn. 3

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this is what i did

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calculated the gradient of ab

alpine sable Jul 11, 2021, 3:36 PM

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As Fig. 2-44 shows, Clara jumps from a bridge, followed closely by Jim. How long did Jim wait after Clara jumped? Assume that Jim is 170 cm tall and that the jumping-off level is at the top of the figure. Make scale measurements directly on the figure.

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How can I know which woman is Clara?

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It's even hard to tell how many women there are in this picture

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At least 2?

rigid smelt Jul 11, 2021, 3:37 PM

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noble stone calculated the gradient of ab

You know that AB is parallel to CD, what can you conclude from their slopes?

noble stone Jul 11, 2021, 3:39 PM

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bruh im embarrassed

alpine sable Jul 11, 2021, 3:56 PM

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anyone able to show me how to use the tabular method to solve the intergral

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im not concerned about the summation at the end, im just concerned about intergation

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i keep on doing it wrong, in multiple different ways, and im just curious to see what the proper way is

rigid smelt Jul 11, 2021, 3:58 PM

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The tabular method as in the DI method?

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The one where you draw the table with two columns

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Just making sure

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And also, post your work

alpine sable Jul 11, 2021, 4:00 PM

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yeah its the two columns, you wanna see all three pages back and forth?

rigid smelt Jul 11, 2021, 4:00 PM

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Ok nvm then

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So, first thing first

alpine sable Jul 11, 2021, 4:01 PM

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rigid smelt Jul 11, 2021, 4:01 PM

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Lets see what we should integrate, and what we should differentiate

alpine sable Jul 11, 2021, 4:01 PM

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this is what ive done so far

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on my latest work

rigid smelt Jul 11, 2021, 4:02 PM

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Ok, seems like you are not sure which one is to be differentiated and which is to be integrated

alpine sable Jul 11, 2021, 4:02 PM

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yes, im not quite sure 😛

rigid smelt Jul 11, 2021, 4:02 PM

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Usually you want to differentiate something that can lead you to 0

alpine sable Jul 11, 2021, 4:02 PM

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x^17 then

rigid smelt Jul 11, 2021, 4:02 PM

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Yes

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So that means you integrate the e^(...)

alpine sable Jul 11, 2021, 4:02 PM

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so to solve this i would have to do the table 17 times?

rigid smelt Jul 11, 2021, 4:03 PM

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Ok but be careful here

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Yes thats the problem

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Usually there is also a shortcut

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Lets look at the integral of e^(1+x^9)

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Oh wait actually

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lets first try to seperatethings out a bit

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So check out e^(1+x^9)

alpine sable Jul 11, 2021, 4:05 PM

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yep thats e^1 * e^9

rigid smelt Jul 11, 2021, 4:05 PM

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The derivative of that is e^(...) * (9x^8)

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So maybe if we can have x^8 multiplied to e^(...) that would be nice

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So lets take x^8 out of x^17

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What do we get?

alpine sable Jul 11, 2021, 4:06 PM

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lemme read this and try to understand so gimmie a sec

rigid smelt Jul 11, 2021, 4:07 PM

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rigid smelt So maybe if we can have x^8 multiplied to e^(...) that would be nice

The reason for this is because the anti-derivative of 9x^8 * e^(...) is exactly e^(...)

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It makes it easier to integrate

alpine sable Jul 11, 2021, 4:08 PM

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is it possible to write this out so i can see it?

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because im a bit confused haha

rigid smelt Jul 11, 2021, 4:08 PM

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Uhh im not near some papers

alpine sable Jul 11, 2021, 4:08 PM

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alright 🙂 yeah i understand

rigid smelt Jul 11, 2021, 4:08 PM

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Ok, so basically integrating is like the inverse of differentiating

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If we know that f' is a derivative of f

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Then we know that if we integrate f' we get f

rigid smelt Jul 11, 2021, 4:09 PM

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rigid smelt The reason for this is because the anti-derivative of 9x^8 * e^(...) is exactly ...

So this is the reason why i want this

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Are you clear?

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Because we will be integrating something right?

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So we need to choose something that is easy to integrate

alpine sable Jul 11, 2021, 4:11 PM

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im just confused, essentially i need to simpfliy the problem to get something easier to intergrate correct?

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is what im guessing here 😛

rigid smelt Jul 11, 2021, 4:11 PM

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Yes

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Exactly

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You want to choose a function that is easy to integrate

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Because differentiate is easy, it does not take much effort

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Whereas integration is not

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Thats where we should be careful

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Right

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So

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Can you take x^8 out of x^17

alpine sable Jul 11, 2021, 4:12 PM

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jesus christ yes you can

rigid smelt Jul 11, 2021, 4:13 PM

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And what is left

alpine sable Jul 11, 2021, 4:13 PM

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okay so you have 2x^17e^1+x^9

rigid smelt Jul 11, 2021, 4:13 PM

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When you factored x^8 out of x^17

alpine sable Jul 11, 2021, 4:14 PM

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this is where im bad at math hoenstly is with stuff like this

rigid smelt Jul 11, 2021, 4:15 PM

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You just need to divide x^17 by x^8

alpine sable Jul 11, 2021, 4:16 PM

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so it wouls be 2x^17/8

rigid smelt Jul 11, 2021, 4:16 PM

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No...wrong rule

alpine sable Jul 11, 2021, 4:16 PM

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haha, i feel so dumb rn

rigid smelt Jul 11, 2021, 4:16 PM

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x^a/x^b = x^(a-b)

alpine sable Jul 11, 2021, 4:16 PM

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2x^9e^(1+x)

rigid smelt Jul 11, 2021, 4:17 PM

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Almost correct

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2x^9 * x^8e^(1+x^9)

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So like we said earlier, we are going to differentiate 2x^9, since it will lead to 0

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But the main reason is, x^8e^(1+x^9) is easy to integrate

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Now do that on the table

alpine sable Jul 11, 2021, 4:18 PM

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ahhh okay, bro i get it. thank you so much

rigid smelt Jul 11, 2021, 4:18 PM

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Its not done yet but ok

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Be careful because you are not going to reach 0, youll have to stop at a point during the process

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You'll undsrstand what i mean

alpine sable Jul 11, 2021, 4:19 PM

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it will stop when the products are either the same as the orginal or you can intergrate the steps 😛

rigid smelt Jul 11, 2021, 4:20 PM

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Yep

alpine sable Jul 11, 2021, 4:20 PM

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my sons just woke up, so i have to fnish it later

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thanks for the help 🙂

leaden jetty Jul 11, 2021, 4:34 PM

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is this possible in maths ?
Example
2+0 = 2
....
....
2+3 = 5
....
....
2+7 = 9
Here [2,3],[2,7],[2,0] are addends. If i were to keep 1 addend fixed, in the above case 2, and the other addend within limit 0 -7. From the output of these addends sum. can we get obtain 2 which is common addend ?

charred flint Jul 11, 2021, 4:35 PM

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not sure what you mean

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you can't retrieve 2 from the numbers {2,3,4,5,6,7,8,9}

leaden jetty Jul 11, 2021, 4:41 PM

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but some folk said they can,
sum of outputs = 44
sum of addend [0-7] = 28
no of values = [0-7] = 8
so (44-28)/8 ?

marble moat Jul 11, 2021, 4:44 PM

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can some one prove this wrong?
because it ofc isnt right.. but idk how its wrong either

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<@&286206848099549185>

leaden jetty Jul 11, 2021, 4:57 PM

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charred flint you can't retrieve 2 from the numbers {2,3,4,5,6,7,8,9}

why?
can't we determine all possibilities for each {2,3,4,5,6,7,8,9} and determine the common one in all of the 2nd addends, since we already have information that the 1st addend is constant.? Wouldn't that determine 2 as the constant addend

charred flint Jul 11, 2021, 4:58 PM

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@marble moat it's right, because in the usual number system there's no number between 99.9999... and 100

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@leaden jetty oh sure, if you know {2,3,4,5,6,7,8,9} and the addends were [0-7] plus a constant, then you can get 2 like that

leaden jetty Jul 11, 2021, 5:02 PM

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charred flint <@!792598153118613514> oh sure, if you know {2,3,4,5,6,7,8,9} and the addends we...

but there is a problem, i get 0 and 2 as common addends in the above scenario. Is that suppose to happen ?

charred flint Jul 11, 2021, 5:02 PM

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how do you get 0 from (44-28)/8 ?

leaden jetty Jul 11, 2021, 5:02 PM

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charred flint how do you get 0 from (44-28)/8 ?

not that i meant this.
#help-0 message

charred flint Jul 11, 2021, 5:03 PM

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I don't follow

leaden jetty Jul 11, 2021, 5:08 PM

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charred flint I don't follow

{2,3,4,5,6,7,8,9} i want to extract the common addend from this output,
we know that second addend have a limit [0-7] and first addend is constant. That's all the information we know.
from the outputs {2,3,4,5,6,7,8,9}
2 possible states [2+0],[0+2],[1+1]
3 possible states [0+3],[3+0],[2+1],[1+2]
similarly ....
all up to 9
if we were to take the common addends among all these states , we find 0 and 2 as common

charred flint Jul 11, 2021, 5:09 PM

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to get 9 you need 2+7 right?

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I don't know how to use 0 for that

leaden jetty Jul 11, 2021, 5:09 PM

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or 0+9

charred flint Jul 11, 2021, 5:10 PM

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well [0-7] is the limit

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and 9 is outside of that

leaden jetty Jul 11, 2021, 5:10 PM

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aaah my bad

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do you know what formula is this ?
#help-0 message

charred flint Jul 11, 2021, 5:14 PM

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adding up everything to solve for the constant?

leaden jetty Jul 11, 2021, 5:15 PM

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yes

charred flint Jul 11, 2021, 5:19 PM

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I don't think it has a name

alpine sable Jul 11, 2021, 5:20 PM

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52 = d_0 - gt_0^2 * 1/2 where d_0 is the distance she fell w/o parachute and t\0 is the time she fell w/o parachute.

So her velocity is y' = -gt, and so at t_0, we have that y'(t_0) = -gt_0.

We can now define her position as she falls with the parachute: y = 52 - gt_0 t - at^2 * 1/2, where a = 2.10 m/s^(2).

So then we have v^2 = v^(2)_0y + 2ay, where a = -9.8 and y = -d_0 (I guess since she falls the distance), so g^2 t^(2)_0 = 2gd_0. Then at t_1, she fell down to 0 from 52 meters so 0 = 52 - gt_0 t_1 - at^(2)_1 * 1/2 or (2d_1 - 2d_0)/-g = t^(2)_0.

But this doesn't make any sense because this implies that 2d_0 - 2\d_1 = 2d_0.

Where's the mistake?

shrewd otter Jul 11, 2021, 5:24 PM

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52 = d_0 - gt_0^2 * 1/2 where d_0 is the distance she fell w/o parachute and t\0 is the time she fell w/o parachute.
52 is d_0.

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The rest of the formulae are hard to read in ASCII so I can't comment further.

alpine sable Jul 11, 2021, 5:27 PM

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yeah ^. y=y(0)-(1/2)gt, y here represents the height recorded from the ground not from above, which means that if we want for example a situation of the parachutist on the ground, we'd do y=0, and not y=52, because 0 is the height recorded from the ground.

shrewd otter Jul 11, 2021, 5:28 PM

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No, we need to find the initial height.

alpine sable Jul 11, 2021, 5:28 PM

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shrewd otter > 52 = d_0 - gt_0^2 * 1/2 where d_0 is the distance she fell w/o parachute and t...

How is that?

shrewd otter Jul 11, 2021, 5:28 PM

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The question says so.

alpine sable Jul 11, 2021, 5:28 PM

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She fell 52.,0m after bailing out

shrewd otter Jul 11, 2021, 5:28 PM

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Yes.

alpine sable Jul 11, 2021, 5:29 PM

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bail out
phrasal verb of bail

1.
scoop water out of a boat or ship.
"the first priority is to bail out the boat with buckets"
2.
make an emergency parachute descent from an aircraft.

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So she fell 52.0 meters with the parachute

shrewd otter Jul 11, 2021, 5:29 PM

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No...

alpine sable Jul 11, 2021, 5:29 PM

#

???

shrewd otter Jul 11, 2021, 5:29 PM

#

She fell withouit friction.

#

Meaning she didn't open the parachute for those 52 meters.

tough hatch Jul 11, 2021, 5:29 PM

#

to clear this up, "falls 52.0 m without friction" doesn't meaning falling to the ground from 52.0m .

shrewd otter Jul 11, 2021, 5:30 PM

#

She jumped from x to x - 52.

alpine sable Jul 11, 2021, 5:30 PM

#

But it says after bailing out

#

Which makes me think the parachute is deployed

tough hatch Jul 11, 2021, 5:30 PM

#

shrewd otter She jumped from x to x - 52.

this is correct

shrewd otter Jul 11, 2021, 5:30 PM

#

I believe "bailing out" could be interpreted to just mean "jumping out".

alpine sable Jul 11, 2021, 5:30 PM

#

The wording of this question made me waste so much time

#

I am so mad right now

#

What is the awnser to: "Biologists found a new species of pale shrimp at the world's deepest undersea vent, the Beebe Vent Field. The vent is 3.1 miles below the sea's surface. Approximately how many kilometers below the sea's surface is the vent? (1 kilometer≈ 0.6214 miles)" if the choices are 2, 3, 4 and 5?

#

Apparently it's 5, but I don't understand how it's not 2

tough hatch Jul 11, 2021, 5:31 PM

#

no, they worded the question just fine

#

it is simply easy to assume that they fell 52.0m above ground level

shrewd otter Jul 11, 2021, 5:31 PM

#

alpine sable The wording of this question made me waste so much time

I feel like you just read into the questions too much, at least from my limited experience talking to you.

alpine sable Jul 11, 2021, 5:32 PM

#

😮‍💨

barren shoal Jul 11, 2021, 5:45 PM

#

n of Water bottles sold -dependent
temperature reading - independent

body mass (kg) - dependent
energy requirement - independent.

Do these independent/dependent variables look correct?

shrewd otter Jul 11, 2021, 5:48 PM

#

body mass (kg) - dependent
energy requirement - independent.

shrewd otter Jul 11, 2021, 5:48 PM

#

barren shoal n of Water bottles sold -dependent temperature reading - independent body m...

These two don't seem correct.

barren shoal Jul 11, 2021, 5:48 PM

#

I thought so, thank you.

#

One more:

Time (Years) - Independent
Movie Tickets ($) - Dependent

#

This should be correct, right? because time cannot be changed by ticket prices but time can affect movie ticket prices as they increase over the years.

shrewd otter Jul 11, 2021, 5:54 PM

#

barren shoal This should be correct, right? because time cannot be changed by ticket prices b...

The way I see it, a reading or measurement is independent.

#

Whereas, as you pointed out, the price of movie tickets depends on time, as well as the economy.

#

If you can express the quantity as a function of something else, it is dependent.

#

f(x) = y.

#

x is the independent variable, y is the dependent one.

barren shoal Jul 11, 2021, 5:57 PM

#

ahh. this makes sense, thank you good sir.

shrewd otter Jul 11, 2021, 5:57 PM

#

Cheers.

small depot Jul 11, 2021, 6:04 PM

#

Can someone here who is familiar with Propositional Logic help me understand how Tautologies are denoted?

#

I'm confused on the specifics of this statement, In propositional logic, a tautology is a proposition that is true by virtue of its truth-functional form. As such, ¬P is patently not a tautology

#

I understand that this is saying a tautology by definition is a truth function with a truth table with only True values.

#

However, what does this mean in the context of some ¬P?

#

If instead of ¬P, it was P, can we define this P as a tautology?

clever locust Jul 11, 2021, 6:08 PM

#

Well if P is always true, then ¬P is always false

small depot Jul 11, 2021, 6:09 PM

#

Or perhaps I'm confused on that: the issue isn't "P" per say, but rather if "P" implies P being always True, or if "P" implies a proposition like "A∨¬A"?

#

Expressly that if P implies being always True, then ¬P is always false. But if "P" refers to a proposition like "A∨¬A", then "P" is a tautology?

clever locust Jul 11, 2021, 6:10 PM

#

Well A \/ ¬A is an example of a tautology

#

So yes

small depot Jul 11, 2021, 6:11 PM

#

My question is, is it simply not notationally correct to refer to some "P" as a tautology?

clever locust Jul 11, 2021, 6:11 PM

#

If P refers to A \/ ¬A, then P is a tautology

small depot Jul 11, 2021, 6:11 PM

#

And furthermore, what is the correct way to denote that "P" is a tautology?

clever locust Jul 11, 2021, 6:11 PM

#

By saying that P is a tautology

small depot Jul 11, 2021, 6:12 PM

#

Is there no symbolic representation? Wikipedia seems to imply that this is denoted as ⊤(P) or ⊨P

#

Are any of these "correct"?

clever locust Jul 11, 2021, 6:12 PM

#

Everything doesn't need a symbolic representation, and overusing symbols can become quite obnoxious

#

And I'm sorry to say but I don't know any symbolic representation for it

#

But if those are on wikipedia, they are probably used by at least some people

small depot Jul 11, 2021, 6:14 PM

#

I see, thank you. I have never studied logic before. I assume you have, and it is not common practice to explicitly denote tautologies?

clever locust Jul 11, 2021, 6:14 PM

#

I have only done some basic logic myself as well so I'm not the right person to ask for that really

small depot Jul 11, 2021, 6:15 PM

#

I see, thanks. If anyone else knows, please feel free to answer.

clever locust Jul 11, 2021, 6:15 PM

#

You could try asking in #proofs-and-logic if you want to

small depot Jul 11, 2021, 6:16 PM

#

Ah alright, that's a good idea.

alpine sable Jul 11, 2021, 6:26 PM

#

I'm still confused by this question

#

Look, if we define y_p to be the position when she activates the parachute, then $y_p = d_1 - d_0 + y_p'(0) - 2.1/2 t^2$

ocean sealBOT Jul 11, 2021, 6:27 PM

#

n/c

alpine sable Jul 11, 2021, 6:28 PM

#

And we can see that y'p = -31.9 with previous work

#

So then $t = \frac{y_p' - y_p'(0)}{-a}$

ocean sealBOT Jul 11, 2021, 6:28 PM

#

n/c

alpine sable Jul 11, 2021, 6:29 PM

#

But then we have that $\frac{2.9 + 31.9}{-2.1} < 0$, which makes no sense for time?!?!

ocean sealBOT Jul 11, 2021, 6:29 PM

#

n/c

vagrant rover Jul 11, 2021, 6:32 PM

#

If the principal of your school wanted to know the average time students spent studying each week, she/he should use a sample.
Should the principle use a sample or a population?

alpine sable Jul 11, 2021, 6:44 PM

#

<@&286206848099549185>

alpine sable Jul 11, 2021, 7:27 PM

#

Any helpers available for my question?

median leaf Jul 11, 2021, 7:44 PM

#

sully sully sully sully

charred flint Jul 11, 2021, 7:48 PM

#

uh for most physics questions just flip the sign to fix it

clever locust Jul 11, 2021, 7:50 PM

#

alpine sable But then we have that $\frac{2.9 + 31.9}{-2.1} < 0$, which makes no sense for ti...

Now I haven't read the entirety of what you've written, but you use a=2.1 here, which is clearly wrong and should be a=-2.1 as she decelerates, implying a negative acceleration

alpine sable Jul 11, 2021, 7:51 PM

#

clever locust Now I haven't read the entirety of what you've written, but you use a=2.1 here, ...

No, I used a = 2.1, so it's the acceleration

#

And so we use -a instead of a in the formula

clever locust Jul 11, 2021, 7:51 PM

#

Eh I think that's a bit misleading then

alpine sable Jul 11, 2021, 7:53 PM

#

I am learning abt polynomials can a polynomial have a variable as its exponent?

clever locust Jul 11, 2021, 7:53 PM

#

You mean something like 2^x?

alpine sable Jul 11, 2021, 7:53 PM

#

yeah

clever locust Jul 11, 2021, 7:53 PM

#

That's an exponential and not a polynomial

#

But you can have that

alpine sable Jul 11, 2021, 7:54 PM

#

So you can't have a variable as its exponent meaning it isn't a polynomial?

clever locust Jul 11, 2021, 7:54 PM

#

Yeah if the variable is in the exponent it is an exponential function and not a polynomial

#

A polynomial is specifically when you have x to some constant positive integer power

alpine sable Jul 11, 2021, 7:55 PM

#

o ok also uh I heard squart root 2 is a polynomial since its constant

#

but square root 1 isnt

#

how is square root 2 a poly?

thick flame Jul 11, 2021, 7:56 PM

#

sqrt 1 is though

alpine sable Jul 11, 2021, 7:56 PM

#

since square root 2 is a decimal?

thick flame Jul 11, 2021, 7:56 PM

#

clever locust A polynomial is specifically when you have x to some constant positive integer p...

also I think the power doen't need to be an integer, and only needs to be >= 0

alpine sable Jul 11, 2021, 7:56 PM

#

could you tell me the def of constant again?

#

im summer schooling algebra 1 rn and uh im 13 so like .

#

help.

clever locust Jul 11, 2021, 7:57 PM

#

thick flame also I think the power doen't need to be an integer, and only needs to be >= 0

Actually they do need to be integers, but yeah >=0 is enough

thick flame Jul 11, 2021, 7:57 PM

#

oof yeah just remembered the int thing

clever locust Jul 11, 2021, 7:57 PM

#

So non-negative integer powers

thick flame Jul 11, 2021, 7:57 PM

#

yeah

thick flame Jul 11, 2021, 7:57 PM

#

alpine sable could you tell me the def of constant again?

constant is a non changing value

clever locust Jul 11, 2021, 7:58 PM

#

alpine sable could you tell me the def of constant again?

A constant is just the opposite of a variable, so a fixed number. For instance 3 could be a constant

alpine sable Jul 11, 2021, 7:58 PM

#

so decimals can be constant? and fractions?

thick flame Jul 11, 2021, 7:58 PM

#

alpine sable how is square root 2 a poly?

sqrt 2 can be a poly because it's = sqrt 2 * x^0

thick flame Jul 11, 2021, 7:58 PM

#

alpine sable so decimals can be constant? and fractions?

yes

alpine sable Jul 11, 2021, 7:58 PM

#

why isnt sqrt 1 a poly?

elfin snow Jul 11, 2021, 7:58 PM

#

any number is a constant

thick flame Jul 11, 2021, 7:58 PM

#

alpine sable why isnt sqrt 1 a poly?

sqrt 1 is a poly

clever locust Jul 11, 2021, 7:58 PM

#

sqrt(1) is a polynomial because it is only a constant

alpine sable Jul 11, 2021, 7:58 PM

#

OH

elfin snow Jul 11, 2021, 7:58 PM

#

the word constant means unchanging, and numbers dont change but variables can

alpine sable Jul 11, 2021, 7:59 PM

#

OHhh i was reading mathisfun and I misread it alr alr thanks!

clever locust Jul 11, 2021, 7:59 PM

#

So you have

$$\sqrt{1}=\sqrt{1}x^0$$

and as $0$ is a non-negative integer constant, it is a polynomial

ocean sealBOT Jul 11, 2021, 7:59 PM

#

Lorago

alpine sable Jul 11, 2021, 7:59 PM

#

ah also last thing for a poly degree it would only be the variables the largest variables right since numbers only have a degree of 0

clever locust Jul 11, 2021, 8:00 PM

#

Yes, the degree of the polynomial is the largest exponent

alpine sable Jul 11, 2021, 8:00 PM

#

ok thanks.

clever locust Jul 11, 2021, 8:00 PM

#

So sqrt(1) would be a polynomial of degree 0

thick flame Jul 11, 2021, 8:00 PM

#

(on the variable ofc)

#

2⁶x³ is a valid polynomial but 2⁶ is a constant

clever locust Jul 11, 2021, 8:01 PM

#

Yeah that is important to keep in mind^

alpine sable Jul 11, 2021, 8:01 PM

#

you guys know a website where it tells you every exponent minus and stuff

#

so like

#

3x^2-3c could you do that etc.

clever locust Jul 11, 2021, 8:02 PM

#

So 2⁶x³ is an example of a polynomial of degree 3

alpine sable Jul 11, 2021, 8:02 PM

#

and like 6c^2+6c^4 could you do that

clever locust Jul 11, 2021, 8:02 PM

#

What do you mean?

alpine sable Jul 11, 2021, 8:02 PM

#

clever locust So 2⁶x³ is an example of a polynomial of degree 3

OOH OK

thick flame Jul 11, 2021, 8:02 PM

#

alpine sable you guys know a website where it tells you every exponent minus and stuff

yeah, your question here makes no sense

alpine sable Jul 11, 2021, 8:02 PM

#

clever locust What do you mean?

o since it give me a poly and i need to see the diffrents so I need to know every situation where ik that I can minus this but not that

#

or add this but not that

#

so ill give u a e.g

#

(6c^2+3c+9)-(3c-5)

#

could i minus

#

6c^2-3c

#

or only 3c-3c

thick flame Jul 11, 2021, 8:03 PM

#

you can always add and subtract polynomials

clever locust Jul 11, 2021, 8:04 PM

#

You can always add and subtract, but when you're simplifying, you have to look at the different degree term separately

alpine sable Jul 11, 2021, 8:05 PM

#

alpine sable 6c^2-3c

how is the answer 6c^2+14 I got 6c^2+4 since 9-5 would be +4 ..?

#

is it bc -*- is +

#

making it 9+5

clever locust Jul 11, 2021, 8:06 PM

#

So in your example you add all $c^2$ terms, which is only $6c^2$. Then you add all $c$ terms, which is $3c-3c=0$. Then you add all constant terms, which is $9+5=14$. Adding that all together you get that

$$(6c^2+3c+9)-(3c-5)=6c^2+14$$

ocean sealBOT Jul 11, 2021, 8:06 PM

#

Lorago

clever locust Jul 11, 2021, 8:06 PM

#

Does this make sense?

alpine sable Jul 11, 2021, 8:06 PM

#

uhh

clever locust Jul 11, 2021, 8:06 PM

#

alpine sable making it 9+5

Yes exactly

thick flame Jul 11, 2021, 8:06 PM

#

alpine sable is it bc -*- is +

yes

alpine sable Jul 11, 2021, 8:07 PM

#

oh

#

would the minus effect 6c^2+3c+9

#

making it

#

6c^2-3c-9?

clever locust Jul 11, 2021, 8:09 PM

#

The minus affects what comes after it. So

$$(6c^2+3c+9)-(3c-5)=6c^2+3c+9-3c+5$$

#

Do you follow?

ocean sealBOT Jul 11, 2021, 8:09 PM

#

Lorago

alpine sable Jul 11, 2021, 8:09 PM

#

OHHHH

#

I get it

clever locust Jul 11, 2021, 8:09 PM

#

Great!

alpine sable Jul 11, 2021, 8:10 PM

#

HMP the book is so bad they made it into a minus thingie when i couldve

alpine sable Jul 11, 2021, 8:10 PM

#

clever locust Eh I think that's a bit misleading then

How is it misleading?

clever locust Jul 11, 2021, 8:10 PM

#

alpine sable How is it misleading?

You shouldn't bake your minus-sign into your equation

thick flame Jul 11, 2021, 8:10 PM

#

yeah, the minus sign should be part of the acceleration value

alpine sable Jul 11, 2021, 8:10 PM

#

bc i distribute the negative right

clever locust Jul 11, 2021, 8:11 PM

#

thick flame yeah, the minus sign should be part of the acceleration value

Exactly

alpine sable Jul 11, 2021, 8:11 PM

#

thanks :D

#

can u do -4x^2+8x

#

?

thick flame Jul 11, 2021, 8:12 PM

#

yeah

alpine sable Jul 11, 2021, 8:12 PM

#

wait so you can do anything with subtraction and addition:?

thick flame Jul 11, 2021, 8:13 PM

#

yes

alpine sable Jul 11, 2021, 8:13 PM

#

what would 4x^2-5c^8 be?

thick flame Jul 11, 2021, 8:13 PM

#

4x² - 5c⁸

alpine sable Jul 11, 2021, 8:13 PM

#

oh bc there are 2 diffrent variables?

thick flame Jul 11, 2021, 8:14 PM

#

they don't combine because they are different variables

#

and also because they have different exponents

alpine sable Jul 11, 2021, 8:14 PM

#

but 4x^2-6x^4

#

has diffrent exponents?

thick flame Jul 11, 2021, 8:14 PM

#

yes

#

so they don't combine

alpine sable Jul 11, 2021, 8:14 PM

#

what would the answer be?

thick flame Jul 11, 2021, 8:15 PM

#

they stay separate terms in a multi-term polynomial

#

4x² - 6x⁴

alpine sable Jul 11, 2021, 8:15 PM

#

-4x^2+8x has diffrent exponents?

thick flame Jul 11, 2021, 8:15 PM

#

yes

#

-4x² + 8x¹

#

the 1 exponent is assumed when no exponent is written

alpine sable Jul 11, 2021, 8:16 PM

#

thick flame -4x² + 8x¹

this would be the answer? So you can only subtract and add if they have the same exponent and variable

thick flame Jul 11, 2021, 8:16 PM

#

they only combine if they have the same exponent and variable

#

-4x² + 8x is a simplified polynomial

alpine sable Jul 11, 2021, 8:17 PM

#

what about multiplication and addition?

thick flame Jul 11, 2021, 8:17 PM

#

give an example poly and I'll show you how to multiple

#

poly division is more advanced

alpine sable Jul 11, 2021, 8:18 PM

#

What would be the answer toe (x^3-4x^2+3)+(-3x^3+8x-2)?

alpine sable Jul 11, 2021, 8:18 PM

#

thick flame poly division is more advanced

hmm idk if we will have it on the test

thick flame Jul 11, 2021, 8:18 PM

#

that's an addition problem

#

if you haven't been taught it it's not on the test
unless it's taught between now and the test

alpine sable Jul 11, 2021, 8:19 PM

#

Ok im only on chapter 9.1 and its until 9.6 so maybe itll teach it later on

thick flame Jul 11, 2021, 8:19 PM

#

yeah

alpine sable Jul 11, 2021, 8:19 PM

#

alpine sable What would be the answer toe (x^3-4x^2+3)+(-3x^3+8x-2)?

whats the answer to this?

vagrant rover Jul 11, 2021, 8:20 PM

#

What data values do you need to create a box and whisker plot?
A.
minimum, mean, median, maximum
B.
minimum, mean, median, mode, maximum
C.
minimum, mean, median, lower quartile, upper quartile, maximum
D.
minimum, lower quartile, median, upper quartile, maximum

thick flame Jul 11, 2021, 8:20 PM

#

vagrant rover What data values do you need to create a box and whisker plot? A. minimu...

read #❓how-to-get-help

vagrant rover Jul 11, 2021, 8:20 PM

#

This is D right?

thick flame Jul 11, 2021, 8:20 PM

#

alpine sable whats the answer to this?

you can call it
(x³ - 4x² + 3) + (-3x³ + 8x -2) for readability

#

then evaluate like so

#

distribute the + into the parentheses (nothing happens since distributing + is multiplying by 1)

#

drop the parentheses

#

x³ - 4x² + 3 + -3x³ + 8x -2

#

-3x³ is the same as - 3x³

#

x³ - 4x² + 3 - 3x³ + 8x -2

#

now sort

#

x³ - 3x³ - 4x² + 8x - 2 + 3

#

and simplify

#

x³ - 3x³ = -2x³

2 + 3 = 1

-2x³ - 4x² + 8x +1

alpine sable Jul 11, 2021, 8:24 PM

#

thick flame x³ - 3x³ - 4x² + 8x - 2 + 3

wouldnt it be x^3+3x^3?

#

OHH Wait nvm

thick flame Jul 11, 2021, 8:24 PM

#

yeah

#

you got it, right?

alpine sable Jul 11, 2021, 8:25 PM

#

thick flame x³ - 3x³ - 4x² + 8x - 2 + 3

you can do -4x^2+8x?

strong citrus Jul 11, 2021, 8:25 PM

#

Is this way ok for divisibility induction proofs?

thick flame Jul 11, 2021, 8:25 PM

#

strong citrus Is this way ok for divisibility induction proofs?

#❓how-to-get-help

thick flame Jul 11, 2021, 8:25 PM

#

alpine sable you can do -4x^2+8x?

they won't combine, they are next to eachother as a result of sorting

alpine sable Jul 11, 2021, 8:26 PM

#

oh wait

#

Yeah OO i get it

#

THanks :D:D:D:

thick flame Jul 11, 2021, 8:26 PM

#

:D

alpine sable Jul 11, 2021, 8:26 PM

#

what college do u go to

strong citrus Jul 11, 2021, 8:26 PM

#

thick flame <#488120190538743810>

?

thick flame Jul 11, 2021, 8:26 PM

#

strong citrus ?

read the rules for the questions channels

wooden cloud Jul 11, 2021, 8:26 PM

#

is the limit of f(x) as x approaches inf or -inf existent?

alpine sable Jul 11, 2021, 8:27 PM

#

how would I do this problem.. 'Find the sum f(x) + g(x) and the diffrence f(x)-g(x) for the functions f(x) = 3x^2+x-7 and g(x) = -x^2+5x-2?

thick flame Jul 11, 2021, 8:27 PM

#

substitute the polynomials in place of f(x) and g(x)

alpine sable Jul 11, 2021, 8:27 PM

#

oh do

#

ohh SO

#

its be w

#

(3x^2+x-7)+(-x^2+5x-2)

#

oh wait

thick flame Jul 11, 2021, 8:28 PM

#

include parentheses

thick flame Jul 11, 2021, 8:28 PM

#

alpine sable (3x^2+x-7)+(-x^2+5x-2)

yes this is f(x) + g(x)

alpine sable Jul 11, 2021, 8:29 PM

#

and for the diffrence instead of addition sign itll be -

#

oohhhh THAnks

thick flame Jul 11, 2021, 8:29 PM

#

yes

alpine sable Jul 11, 2021, 8:29 PM

#

ok 9.2

strong citrus Jul 11, 2021, 8:31 PM

#

thick flame yes

Bro?

thick flame Jul 11, 2021, 8:31 PM

#

strong citrus Bro?

sup

strong citrus Jul 11, 2021, 8:31 PM

#

Which rules am I missing?

thick flame Jul 11, 2021, 8:32 PM

#

you initially missed
2. Before asking a question, make sure that the channel you are using is not currently in use. ...

strong citrus Jul 11, 2021, 8:32 PM

#

thick flame you initially missed `2. Before asking a question, make sure that the channel y...

Is channel free now?

thick flame Jul 11, 2021, 8:33 PM

#

strong citrus Is channel free now?

looks to be so, but you should stick to #help-1 where it's posted rn

strong citrus Jul 11, 2021, 8:33 PM

#

thick flame looks to be so, but you should stick to <#269573202018041856> where it's posted ...

Wut I just deleted it

vagrant rover Jul 11, 2021, 8:33 PM

#

What data values do you need to create a box and whisker plot?
A.
minimum, mean, median, maximum
B.
minimum, mean, median, mode, maximum
C.
minimum, mean, median, lower quartile, upper quartile, maximum
D.
minimum, lower quartile, median, upper quartile, maximum

It's D ,Right?

strong citrus Jul 11, 2021, 8:34 PM

#

Yup

vagrant rover Jul 11, 2021, 8:35 PM

#

strong citrus Yup

Are yo utalking to me?

strong citrus Jul 11, 2021, 8:36 PM

#

strong citrus Is this way ok for divisibility induction proofs?

Sir @thick flame I am sorry if I offended you by not following the rules but can you please tell me if this way of proof divisibility induction is correct or not?

vagrant rover Jul 11, 2021, 8:36 PM

#

Bro just post your question, he's being a Karen

strong citrus Jul 11, 2021, 8:36 PM

#

vagrant rover Bro just post your question, he's being a Karen

???

vagrant rover Jul 11, 2021, 8:37 PM

#

Ask your quesition, it's okay

#

When I try to calculate the variance I am getting: 1.6784 , but that isn't one of the answers. Am I getting the variance correctly or am I doing it wrong?

#

I am calculating as a population and not as a sample. Should I be calculating as a sample or as a population?

thick flame Jul 11, 2021, 9:09 PM

#

vagrant rover When I try to calculate the variance I am getting: `1.6784 `, but that isn't one...

It should be sample since the selection isn't the whole population IIRC

vagrant rover Jul 11, 2021, 9:11 PM

#

Ah, okay. So I'm getting 1.7126, but that isn't one of the answers either. Should I just put down D? or is there something I'm missing?

#

@thick flame

thick flame Jul 11, 2021, 9:12 PM

#

idk, it doesn't say to round but one would guess you should round to a certain degree?
not entirely sure why they didn't specify

#

wait

#

an option is 1.31 though

vagrant rover Jul 11, 2021, 9:13 PM

#

Yeah, that's why I'm confused, they usually specify if I need to round or not, but I guess not here.

thick flame Jul 11, 2021, 9:13 PM

#

so rounding to 10ths makes no sense

vagrant rover Jul 11, 2021, 9:13 PM

#

wym?

#

oh

#

sec lemme check something

thick flame Jul 11, 2021, 9:13 PM

#

hmm

vagrant rover Jul 11, 2021, 9:14 PM

#

Yeah idk]

#

There are instances where the test is wrong so maybe that's just the problem here

#

I don't think there is a better answer so I'll just put 1.7

#

also,I have stupid question

thick flame Jul 11, 2021, 9:16 PM

#

ask away

vagrant rover Jul 11, 2021, 9:16 PM

#

``` I have this data set, and I need to calculate the percentage of values that are more than 1 standard deviation from the mean

#

So I got whihc ones

#

and they are 4

#

So if I wanted to tget the percentage I do 4/14

#

Right?

thick flame Jul 11, 2021, 9:17 PM

#

yes

vagrant rover Jul 11, 2021, 9:17 PM

#

Okok, not 14/4

thick flame Jul 11, 2021, 9:17 PM

#

that's a decimal value

vagrant rover Jul 11, 2021, 9:17 PM

#

yeah?

thick flame Jul 11, 2021, 9:17 PM

#

vagrant rover So if I wanted to tget the percentage I do 4/14

the decimal value is correct here

vagrant rover Jul 11, 2021, 9:17 PM

#

Ah okay oaky, awesome, ty!

echo python Jul 11, 2021, 9:36 PM

#

say I have coordinates x and y as (0, 0), angle as 150 degrees and distance as 30, how would I calculate the new coordinates?

slate kayak Jul 11, 2021, 9:39 PM

#

Stop

#

<@&268886789983436800>

#

Stop

tall wing Jul 11, 2021, 9:39 PM

#

banned

ashen wave Jul 11, 2021, 9:41 PM

#

Can anyone help me?

soft tiger Jul 11, 2021, 9:42 PM

#

Not sure you are allowed to post questions while chat is in discussion/unanswered question lol

ashen wave Jul 11, 2021, 9:42 PM

#

oh whoops

#

I thought they were done sorry

echo python Jul 11, 2021, 9:44 PM

#

echo python say I have coordinates x and y as (0, 0), angle as 150 degrees and distance as ...

this might help

#

should be 120 not 30

soft tiger Jul 11, 2021, 9:45 PM

#

alright I guess just disregard the rules lol

topaz scaffold Jul 11, 2021, 9:55 PM

#

Is there any f(x) = g(x) that is true for only a < x < b where |a| and |b| ≠ infinity

glass lichen Jul 11, 2021, 10:01 PM

#

topaz scaffold Is there any f(x) = g(x) that is true for only a < x < b where |a| and |b| ≠ inf...

yes, make f and g piecewise

topaz scaffold Jul 11, 2021, 10:01 PM

#

Continuous, sorry

#

Forgot to include that

clever locust Jul 11, 2021, 10:11 PM

#

You can have piecewise continuous functions yes

alpine sable Jul 11, 2021, 10:14 PM

#

hi guys, i have a curvature equation but its in terms of k(t), i want to find the curvature at a point (0,0,0), how do i get the t value to plug it in?

topaz scaffold Jul 11, 2021, 10:15 PM

#

clever locust You can have piecewise continuous functions yes

Not piecewise either then oof

#

Sorry

clever locust Jul 11, 2021, 10:18 PM

#

What's wrong with piecewise functions? thonkzoom

topaz scaffold Jul 11, 2021, 10:19 PM

#

It's just not what I'm looking for 😅

clever locust Jul 11, 2021, 10:21 PM

#

If you let a ≤ x ≤ b, then it's easy to find such functions

#

Not so sure with strict inequalities though

topaz scaffold Jul 11, 2021, 10:22 PM

#

clever locust If you let a ≤ x ≤ b, then it's easy to find such functions

Well then you can set a=b and do an intersection

#

Also throw out anything with absolute values

clever locust Jul 11, 2021, 10:23 PM

#

Well you could also consider something like

$$f(x)=-x^2+1$$

and

$$g(x)=\sqrt{x^4-2x^2+1}$$

which are equal iff $x\in[-1,1]$

ocean sealBOT Jul 11, 2021, 10:23 PM

#

Lorago

clever locust Jul 11, 2021, 10:29 PM

#

Actually, now that I think about it, I don't think it is possible to have some continuous functions f,g : R -> R such that f(x)=g(x) iff a<x<b for some a,b in R that are not equal

topaz scaffold Jul 11, 2021, 10:30 PM

#

Nice

clever locust Jul 11, 2021, 10:30 PM

#

I don't think it would be too hard to prove

topaz scaffold Jul 11, 2021, 10:30 PM

#

ocean seal **Lorago**

Kinda same effect as the absolute value

clever locust Jul 11, 2021, 10:30 PM

#

But the continuity part does cause trouble there

topaz scaffold Jul 11, 2021, 10:30 PM

#

clever locust I don't think it would be too hard to prove

I have no idea how to do proofs

clever locust Jul 11, 2021, 10:30 PM

#

topaz scaffold Kinda same effect as the absolute value

Actually that is exactly what it is haha

clever locust Jul 11, 2021, 10:30 PM

#

topaz scaffold I have no idea how to do proofs

Well, just keep studying math and eventually you will

strong furnace Jul 11, 2021, 10:31 PM

#

topaz scaffold Is there any f(x) = g(x) that is true for only a < x < b where |a| and |b| ≠ inf...

this is the problem yeah?

topaz scaffold Jul 11, 2021, 10:31 PM

#

Yep

topaz scaffold Jul 11, 2021, 10:31 PM

#

clever locust Well, just keep studying math and eventually you will

It'll take years tho

#

🥲

strong furnace Jul 11, 2021, 10:32 PM

#

why can't you have 2 functions that have same value in an interval

clever locust Jul 11, 2021, 10:32 PM

#

Why?

strong furnace Jul 11, 2021, 10:32 PM

#

discontinuity is not considered outside of domain

#

if it is not defined at a and b

#

there is no discontinuity

clever locust Jul 11, 2021, 10:32 PM

#

strong furnace why can't you have 2 functions that have same value in an interval

The problem is that the interval is open, and it is if and only if x is in that interval

strong furnace Jul 11, 2021, 10:33 PM

#

clever locust The problem is that the interval is open, and it is if and **only** if x is in t...

again I addressed that in my next message I think

clever locust Jul 11, 2021, 10:33 PM

#

Hm I mean actually you could just define the functions on open intervals to begin with, yeah

#

That should work

clever locust Jul 11, 2021, 10:33 PM

#

clever locust Actually, now that I think about it, I don't think it is possible to have some c...

I still believe this though

topaz scaffold Jul 11, 2021, 10:33 PM

#

I only follow about half way here

strong furnace Jul 11, 2021, 10:34 PM

#

nvm

clever locust Jul 11, 2021, 10:34 PM

#

Specifically with f,g : R -> R

strong furnace Jul 11, 2021, 10:34 PM

#

I yeah

#

rrealised

#

you can do a proof by contradiction then

clever locust Jul 11, 2021, 10:34 PM

#

Yeah

#

You could use the definition of continuity there and just do a limit

#

Which should give you the desired contradiction

topaz scaffold Jul 11, 2021, 10:35 PM

#

So I'm assuming the answer is no

clever locust Jul 11, 2021, 10:36 PM

#

If the functions have R (the real numbers) as their domain, then the answer is no

topaz scaffold Jul 11, 2021, 10:38 PM

#

So you're implying that this doesn't hold for complex numbers? 👀

clever locust Jul 11, 2021, 10:39 PM

#

Things are not as simple with complex numbers lol

vast bobcat Jul 11, 2021, 10:47 PM

#

please ping when you answer, thanks!

vagrant rover Jul 11, 2021, 10:54 PM

#

If you keep a record of the high temperature each day in degrees Fahrenheit and in degrees Celsius for the month of April on Long Island, what would you expect the correlation coefficient to be?
A.
r = ‒1
B.
r = 0
C.
r = 1
D.
‒1 ≤ r ≤ 1

#

How do I get the correlation coefficient without a data set?

#

I don't understand this question

noble sinew Jul 11, 2021, 10:56 PM

#

What does correlation coefficient mean?

vagrant rover Jul 11, 2021, 10:56 PM

#

OHHH

glass lichen Jul 11, 2021, 10:56 PM

#

it's pearson's coefficient

vagrant rover Jul 11, 2021, 10:56 PM

#

It's 1

glass lichen Jul 11, 2021, 10:56 PM

#

and yes

vagrant rover Jul 11, 2021, 10:57 PM

#

Cause there is a strong correlation

noble sinew Jul 11, 2021, 10:57 PM

#

Im aware what it is

glass lichen Jul 11, 2021, 10:57 PM

#

yes, R=1

vagrant rover Jul 11, 2021, 10:57 PM

#

Awesome awesome, okay, thanks!

#

I just understood it now

noble sinew Jul 11, 2021, 10:58 PM

#

vast bobcat please ping when you answer, thanks!

Well how many shirts can you buy and still have money left over (if only buying shirts)? How many shoes can you buy and still have money left over?

#

The answer then follows

vagrant rover Jul 11, 2021, 10:59 PM

#

In a normal distribution, 68% of the data falls between 82 and 88, and the mean is 85. What is the standard deviation?
How do I find the standard deviation without a list of data?

vast bobcat Jul 11, 2021, 10:59 PM

#

you can buy 9 shirts

noble sinew Jul 11, 2021, 10:59 PM

#

Use 68-95-99.7 rule

vast bobcat Jul 11, 2021, 11:00 PM

#

noble sinew Well how many shirts can you buy and still have money left over (if only buying ...

how does that work though? is it just pure logic

noble sinew Jul 11, 2021, 11:01 PM

#

Yes so if we were able to buy 10 then surely we would surely be able to buy 10 of the cheapest items

#

Since we can’t do that then it has to be <10

cobalt ledge Jul 11, 2021, 11:02 PM

#

vagrant rover ```In a normal distribution, 68% of the data falls between 82 and 88, and the me...

I believe there’s a rule that states that 68% of the data will always be within one standard deviation from the mean

vast bobcat Jul 11, 2021, 11:02 PM

#

that's such a simple way of thinking about it

#

thank you

cobalt ledge Jul 11, 2021, 11:03 PM

#

cobalt ledge I believe there’s a rule that states that 68% of the data will always be within ...

So I’m pretty sure you can just subtract 85 from the given endpoints and get your standard deviation, but I could be wrong on that

noble sinew Jul 11, 2021, 11:03 PM

#

It is true for normal distributions, yes

noble sinew Jul 11, 2021, 11:04 PM

#

noble sinew Use 68-95-99.7 rule

In general there is this rule

vagrant rover Jul 11, 2021, 11:04 PM

#

I'm not familiar with this rule

noble sinew Jul 11, 2021, 11:04 PM

#

Where the 3 numbers are respectiavly +-sd, +-2sd, +-3sd

vagrant rover Jul 11, 2021, 11:04 PM

#

thonkzoom I don't understand\

noble sinew Jul 11, 2021, 11:05 PM

#

Google is your friend then

vagrant rover Jul 11, 2021, 11:05 PM

#

Yeah

#

What term do I google?

noble sinew Jul 11, 2021, 11:05 PM

#

noble sinew Use 68-95-99.7 rule

This?

vagrant rover Jul 11, 2021, 11:05 PM

#

oh

#

@noble sinewoh, so 1 standard deviation is the answer?

noble sinew Jul 11, 2021, 11:08 PM

#

You are asked for a sd

vagrant rover Jul 11, 2021, 11:08 PM

#

yeah?

noble sinew Jul 11, 2021, 11:09 PM

#

Is 1 standard deviation a value?

vagrant rover Jul 11, 2021, 11:09 PM

#

I'm confused, here it says: "68%, 95%, and 99.7% of the values lie within one, two, and three standard deviations of the mean, respectively."

noble sinew Jul 11, 2021, 11:10 PM

#

Yes

#

So find the value of sd such that the interval is +-sd?

vagrant rover Jul 11, 2021, 11:10 PM

#

3?

noble sinew Jul 11, 2021, 11:10 PM

#

Si

vagrant rover Jul 11, 2021, 11:11 PM

#

Ah okay

#

Fair enough

#

Thanks 😄

vast bobcat Jul 11, 2021, 11:11 PM

#

can someone help me with another question please thanks

noble sinew Jul 11, 2021, 11:18 PM

#

Some sort of trial and error seems easiest

#

Other methods probably overkill

#

So start from the highest value, is it possible to reach 7? Then proceed to 2nd highest and so on.

vast bobcat Jul 11, 2021, 11:22 PM

#

okay thanks

mellow canyon Jul 11, 2021, 11:28 PM

#

hey, what is the difference between something like arctan and cotan? or sec and arcsin? or csc and arccos?

glass lichen Jul 11, 2021, 11:43 PM

#

mellow canyon hey, what is the difference between something like arctan and cotan? or sec and ...

one is inverse trig and one is the reciprocal trig functions

winter salmon Jul 11, 2021, 11:50 PM

#

i found the solution x=5;x=-3 but i can't get the domain

#

i put in x>3 but it was wrong

ionic jewel Jul 11, 2021, 11:52 PM

#

well the second one has to be x < 7

#

,w x^2-5x+6 >= 0

ocean sealBOT Jul 11, 2021, 11:52 PM

#

Results provided by WolframAlpha

Click here to refine your query online
Upgrade to WolframAlpha Pro!

winter salmon Jul 11, 2021, 11:52 PM

#

OHHHHHHHHHH

#

I FORGOT

ionic jewel Jul 11, 2021, 11:53 PM

#

so x <= 2 and x in [3,7]

urban canyon Jul 11, 2021, 11:58 PM

#

uhh this is correct right

winter salmon Jul 11, 2021, 11:59 PM

#

urban canyon uhh this is correct right

yep

urban canyon Jul 11, 2021, 11:59 PM

#

Ty

vagrant rover Jul 12, 2021, 12:00 AM

#

    A.    
power
    B.    
exponential
    C.    
neither because she needs a correlation coefficient of 1
    D.    
it doesn't matter, both correlation coefficients are close enough to 1```

Is this A?

urban canyon Jul 12, 2021, 12:00 AM

#

and for this i set

m< 2 = m<3 and solve for x then - from 180

winter salmon Jul 12, 2021, 12:01 AM

#

ionic jewel so x <= 2 and x in [3,7]

wait what does x in [3,7] mean? thonkzoom

ionic jewel Jul 12, 2021, 12:02 AM

#

$3\leq x \leq 7$

ocean sealBOT Jul 12, 2021, 12:02 AM

#

bunny

winter salmon Jul 12, 2021, 12:02 AM

#

o

#

ty

drowsy scroll Jul 12, 2021, 12:05 AM

#

#

What do i do here

#

how do i multiply x and 7y, or do i just skip it

tribal geyser Jul 12, 2021, 12:06 AM

#

7xy

drowsy scroll Jul 12, 2021, 12:06 AM

#

ok

vagrant rover Jul 12, 2021, 12:06 AM

#

    A.    
power
    B.    
exponential
    C.    
neither because she needs a correlation coefficient of 1
    D.    
it doesn't matter, both correlation coefficients are close enough to 1```

Is this A?

#

Since the correlation coefficient is closer to 1?

winter salmon Jul 12, 2021, 12:10 AM

#

ionic jewel $3\leq x \leq 7$

wait now im like really confused i put in but it was wrong

vagrant rover Jul 12, 2021, 12:23 AM

#

vagrant rover ```Sam is trying to determine if she should use a power or exponential regressio...

<@&286206848099549185>

tidal heron Jul 12, 2021, 12:46 AM

#

Could someone help explain to me 3c? My thought process is since it is a cot function it would be discontinous at every iteration of n+pi

glass lichen Jul 12, 2021, 1:10 AM

#

tidal heron Could someone help explain to me 3c? My thought process is since it is a cot fun...

cot(x)=cos(x)/sin(x)

tidal heron Jul 12, 2021, 1:14 AM

#

glass lichen cot(x)=cos(x)/sin(x)

Could you please elaborate sorry

glass lichen Jul 12, 2021, 1:15 AM

#

well when is a rational function discontinuous?

tidal heron Jul 12, 2021, 1:16 AM

#

When there is a zero of both the numerator and denominator?

glass lichen Jul 12, 2021, 1:17 AM

#

when the denominator is 0

#

or when both num and denom are 0 at the same time

tidal heron Jul 12, 2021, 1:18 AM

#

Okay I think I am getting it

#

Thank you

glass lichen Jul 12, 2021, 1:20 AM

#

yeah, c is discontinuous when sin(x) = 0 so when x is an integer multiple of pi

tidal heron Jul 12, 2021, 1:21 AM

#

Thank you have a great day

alpine sable Jul 12, 2021, 1:25 AM

#

hey can anyone help me with this question, im super confused

stark grail Jul 12, 2021, 1:25 AM

#

How to solve this ques? TvT

#

and this TVT

#

#

is this permutation or combination?

#

Im so confused🥲

charred flint Jul 12, 2021, 1:38 AM

#

@stark grail permutation, because in the end these are in order, like 75324 or AD722

vagrant rover Jul 12, 2021, 1:38 AM

#

    A.    
power
    B.    
exponential
    C.    
neither because she needs a correlation coefficient of 1
    D.    
it doesn't matter, both correlation coefficients are close enough to 1```

Is this A?
Since the correlation coefficient is closer to 1?

stark grail Jul 12, 2021, 1:41 AM

#

charred flint <@!839081716663451650> permutation, because in the end these are in order, like ...

ok thanks ya~

charred flint Jul 12, 2021, 1:43 AM

#

A seems good, it's a bit subjective though blobsweat

alpine sable Jul 12, 2021, 1:47 AM

#

Could anyone help me with this?

charred flint Jul 12, 2021, 1:50 AM

#

so you multiply -3 by itself 2 times

#

then you multiply that by itself 3 times and put it under a fraction

alpine sable Jul 12, 2021, 1:52 AM

#

charred flint then you multiply that by itself 3 times and put it under a fraction

-3 two times is 9 then 9 three times js 729

#

Wdym put under a fraction

charred flint Jul 12, 2021, 1:53 AM

#

that's what a negative exponent does

#

instead of multiplying you're really dividing (going backwards)

#

so it's 1/729 instead yea

alpine sable Jul 12, 2021, 1:54 AM

#

Thats not one of the answers though

charred flint Jul 12, 2021, 1:54 AM

#

right so don't use -3*-3=9 just yet

#

just think of -3 as a random item

#

what is (-3)^2 times itself 3 times?

mint urchin Jul 12, 2021, 2:13 AM

#

alpine sable Thats not one of the answers though

1/729 is not one of the answers...but there is an answer that is the same value of 1/729.

jagged trout Jul 12, 2021, 2:19 AM

#

alpine sable Could anyone help me with this?

(a^b)^c = a^(b * c)

a^(-n) = 1/(x^n)

combine both to get your answer

tacit mortar Jul 12, 2021, 2:20 AM

#

Hey

#

May i use this channel now

#

True or false question
Would this be false cause
even if numerator cancels in -4
the denominator has one more power of (x+4)

#

and isn't point discontinuity the same as removable?

jagged trout Jul 12, 2021, 2:22 AM

#

,w x²+8x+16=0

ocean sealBOT Jul 12, 2021, 2:22 AM

#

Results provided by WolframAlpha

Click here to refine your query online
Upgrade to WolframAlpha Pro!

jagged trout Jul 12, 2021, 2:24 AM

#

0/0 sounds like L'Hospital could be possible

tacit mortar Jul 12, 2021, 2:24 AM

#

jagged trout 0/0 sounds like L'Hospital could be possible

Yes it can be possible if its true

alpine sable Jul 12, 2021, 2:33 AM

#

can anyone help me think of ideas for my math project

arctic wren Jul 12, 2021, 2:33 AM

#

@tacit mortar to know if f(x) has a discontinuity point you have to do the lim by the left, the limit by the right and the limit of X

severe socket Jul 12, 2021, 2:33 AM

#

hello

#

how do i express this as a single logarithm: log3(5)+3log3(2)-log3(4)

arctic wren Jul 12, 2021, 2:34 AM

#

@severe socket do you know the logarithm properties?

severe socket Jul 12, 2021, 2:35 AM

#

no tbh online school makes me forget everything

arctic wren Jul 12, 2021, 2:35 AM

#

So, i'll try to demonstrate with you

#

First things first , do you know the definition of a logartihm?

severe socket Jul 12, 2021, 2:36 AM

#

ya i think so

arctic wren Jul 12, 2021, 2:36 AM

#

What it is ?

severe socket Jul 12, 2021, 2:37 AM

#

cant explain rlly in words but i know some things about like common bases and stuff

arctic wren Jul 12, 2021, 2:40 AM

#

So you know when we write $log_a x = \alpha $ we are saying that $a^{\alpha} = x$

ocean sealBOT Jul 12, 2021, 2:40 AM

#

Guilhotina

arctic wren Jul 12, 2021, 2:40 AM

#

Right?

severe socket Jul 12, 2021, 2:40 AM

#

yes

arctic wren Jul 12, 2021, 2:40 AM

#

Ok

#

So, let $a^{\alpha} = X $ and $a^{\beta}=Y$

ocean sealBOT Jul 12, 2021, 2:41 AM

#

Guilhotina

arctic wren Jul 12, 2021, 2:43 AM

#

If we multiple $a^{\alpha}$ by $ a^{\beta}$ we'll have $a^{\alpha + \beta} = XY$

ocean sealBOT Jul 12, 2021, 2:43 AM

#

Guilhotina

arctic wren Jul 12, 2021, 2:45 AM

#

From our definition of $a^{\alpha}= X $ we have that $log_a X= \alpha$

ocean sealBOT Jul 12, 2021, 2:46 AM

#

Guilhotina

arctic wren Jul 12, 2021, 2:46 AM

#

Sorry for my mistake

#

So you can to it to find the $log_a Y$ and then apply for the definition of logarithm for $a^{\alpha +\beta} = XY$ and you can find one logarithm property

ocean sealBOT Jul 12, 2021, 2:47 AM

#

Guilhotina

arctic wren Jul 12, 2021, 2:48 AM

#

I hope that you understand it, sorry if i explained bad

severe socket Jul 12, 2021, 2:48 AM

#

got it bro thanks

burnt pond Jul 12, 2021, 2:52 AM

#

hi guys i'm still stupid

#

I asked this question somewhere else

#

#

but can anyone explain to me how to solve question 5(a)

#

I don't know how to start

#

Maybe double angle identities but i'm not sure

arctic wren Jul 12, 2021, 2:57 AM

#

burnt pond Maybe double angle identities but i'm not sure

This is the right path

#

And one tip, dont divide both side by sin theta

burnt pond Jul 12, 2021, 3:08 AM

#

arctic wren And one tip, dont divide both side by sin theta

why not tho?

arctic wren Jul 12, 2021, 3:09 AM

#

burnt pond why not tho?

One- depending on theta you will be dividing by 0 second you will lost a soluction

lethal vortex Jul 12, 2021, 3:23 AM

#

i know that arithmetic has the same difference between numbers

burnt pond Jul 12, 2021, 3:32 AM

#

arctic wren One- depending on theta you will be dividing by 0 second you will lost a soluct...

can you elaborate a little more

#

i'm really completely lost on how to solve this one

left echo Jul 12, 2021, 3:33 AM

#

<@&286206848099549185>

arctic wren Jul 12, 2021, 3:33 AM

#

left echo <@&286206848099549185>

Dont tag helpers before 15 minutes

left echo Jul 12, 2021, 3:33 AM

#

oh

#

ma fault

arctic wren Jul 12, 2021, 3:34 AM

#

@left echo np, take the opportunity to read #❓how-to-get-help and #rules

arctic wren Jul 12, 2021, 3:35 AM

#

burnt pond can you elaborate a little more

So if theta = 0 the sin of theta will be 0 and if you divided by sin of theta youre divinding by zero

#

That is wrong

#

And this equation has 2 soluctions and if you divide by sin x you will not find one of the soluctions one is relationed to sin x and another to cos x

left echo Jul 12, 2021, 3:36 AM

#

arctic wren <@531658382122287105> np, take the opportunity to read <#488120190538743810> a...

i dont see that as a rule

arctic wren Jul 12, 2021, 3:37 AM

#

left echo i dont see that as a rule

It's on #info my mistake

#

Sorry

left echo Jul 12, 2021, 3:38 AM

#

you chillin thanks

burnt pond Jul 12, 2021, 3:49 AM

#

arctic wren And this equation has 2 soluctions and if you divide by sin x you will not find ...

the answers say there are 5 solutions

#

0, pi, 2pi, pi/3, 5pi/3

arctic wren Jul 12, 2021, 3:51 AM

#

burnt pond the answers say there are 5 solutions

Oooo the want the angles I though they just want the soluctions because you can write the solution being X= some angle + 2kpi ou

woeful pulsar Jul 12, 2021, 3:52 AM

#

yeah it says they want angles from 0 to 2pi

arctic wren Jul 12, 2021, 3:52 AM

#

I missread the exercise

gritty gull Jul 12, 2021, 3:58 AM

#

how do you find z value?

dense carbon Jul 12, 2021, 4:07 AM

#

Need solution asap

woeful pulsar Jul 12, 2021, 4:09 AM

#

dense carbon

what methods have you learnt with regards to solving simultaneous equations?

ionic jewel Jul 12, 2021, 4:09 AM

#

the solution is always using matrices

topaz scaffold Jul 12, 2021, 4:11 AM

#

You could but he/she might not know linear algebra although its kinda the same idea

ionic jewel Jul 12, 2021, 4:13 AM

#

yeah they don't if they have that kind of problem but still

topaz scaffold Jul 12, 2021, 4:19 AM

#

dense carbon

Ig multiply the first equation by 5/2 to get 5x - 15y/2 = 35/2
Subtracting that from the second you get 23y/2 = -15/2

#

Then you probably low how to solve for y from there

#

And then you can plug in y to solve for x

#

Idk how to use latex yet, sorry

mint urchin Jul 12, 2021, 4:33 AM

#

finally

#

i solved it

#

so you have to use the elimination method.

#

5x + 4y = 10
2x - 3y = 7
you have to eliminate the x or the y by subtracting

topaz scaffold Jul 12, 2021, 4:36 AM

#

Yea

#

Hopefully my mental math didn't fail me

mint urchin Jul 12, 2021, 4:37 AM

#

Since none of them share the same constant you have to work it out. i chose 2x and 5x. you can multiply 2x by 2.5 so that it will equal 5x. do the same with the rest of the equation. now you have the equation. 5x - 7.5y = 17.5

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lets go back to the drawing board. it will look something like this:
5x + 4y = 10
5x - 7.5y = 17.5

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subtract the equations

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5x - 5x = 0

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4y - (-7.5y) = 4y + 7.5y = 11.5y

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10 - 17.5 = -7.5

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now we have the equation:
11.5y = -7.5

topaz scaffold Jul 12, 2021, 4:39 AM

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Wait isn't this what I said before?

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But in decimal form?

mint urchin Jul 12, 2021, 4:39 AM

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topaz scaffold Wait isn't this what I said before?

yes but im just showing it in more depth

topaz scaffold Jul 12, 2021, 4:39 AM

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Ah oki

mint urchin Jul 12, 2021, 4:40 AM

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to elaborate

topaz scaffold Jul 12, 2021, 4:40 AM

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Go at it

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I just kinda skimmed over ngl

mint urchin Jul 12, 2021, 4:41 AM

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11.5y = -7.5
11.5y/11.5 = -7.5/11.5
therefore y = -15/23

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now we got y it should be very easy to get x

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just use one of the equations to verify. for example, 5x + 4y = 10. substitute y for -15/23 and solve.

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5x + 4(-15/23) = 10
5x + -2 14/23 = 10
5x + -2 14/23 + 2 14/23 = 10 + 2 14/23
5x = 12 14/23
5x/5 = (12 14/23)/5
x = 2 12/23

mint urchin Jul 12, 2021, 4:45 AM

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dense carbon

Therefore, x = 2 12/23 or 58/23 and y = -15/23

rigid smelt Jul 12, 2021, 4:58 AM

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the distance travelled (assuming starting position is 0m) is the antiderivative of the velocity

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hence you can conclude that the area of the triangle is the distance travelled

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there is no need for the value

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like i said

topaz scaffold Jul 12, 2021, 4:59 AM

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It says the particle accelerates from rest

rigid smelt Jul 12, 2021, 4:59 AM

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the area is the distance

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yes

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look at the information you are given

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you are given two angles of the triangle

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can you find the other?

topaz scaffold Jul 12, 2021, 5:00 AM

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rigid smelt there is no need for the value

I'm pretty sure you need it, but the problem says it's 0

rigid smelt Jul 12, 2021, 5:00 AM

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you dont

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look at the triangle, its a 30 60 triangle

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what kind of triangle is that?

topaz scaffold Jul 12, 2021, 5:01 AM

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Oh I see mb mb

rigid smelt Jul 12, 2021, 5:01 AM

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yes

topaz scaffold Jul 12, 2021, 5:02 AM

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Divide the area by sqrt(3)

rigid smelt Jul 12, 2021, 5:02 AM

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yes?

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there are a lot of way to find the area

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either find the other two sides

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by trigs

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or ratio of a 30 60 90 triangle

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or you can find the height of the right triangle

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im helping, you are the one to do it

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im not here to do it for you

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is this a test?

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<@&268886789983436800>

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idk

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its their job to decide

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im just told to ping

tall wing Jul 12, 2021, 5:04 AM

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hi what

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oih

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i see

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sorry

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yes banned

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ty

valid lodge Jul 12, 2021, 5:26 AM

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dont really understand how to even start

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or how to write it more i guess

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cause i understand the zeros as x+1 x-1 and x-4

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just dont really understand how to write it after that

topaz scaffold Jul 12, 2021, 5:29 AM

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It's just multiplied

valid lodge Jul 12, 2021, 5:29 AM

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so x^3

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4x

topaz scaffold Jul 12, 2021, 5:29 AM

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So (x+1)(x-1)(x-4)

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Then you can expand that

valid lodge Jul 12, 2021, 5:30 AM

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oh

tough hatch Jul 12, 2021, 5:30 AM

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dang ez give

tough hatch Jul 12, 2021, 5:30 AM

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topaz scaffold So (x+1)(x-1)(x-4)

nope

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polynomial not equation

topaz scaffold Jul 12, 2021, 5:30 AM

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Oh well

tough hatch Jul 12, 2021, 5:31 AM

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tough hatch dang ez give

no fun in that

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lol

valid lodge Jul 12, 2021, 5:31 AM

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wait

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is it 4x

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or is it 4x^2

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.

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ok im kinda dumb

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x^3-4x^2-x+4

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i think]

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then

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okay well

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thanks i guess i was just thinking into it too much

dim vector Jul 12, 2021, 5:35 AM

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can someone help me?

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Create the equation that corresponds to the following graph, use the letters a and b as unknowns

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linear equations

ionic jewel Jul 12, 2021, 5:36 AM

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dim vector Create the equation that corresponds to the following graph, use the letters a a...

a+b = 5+3?

tough hatch Jul 12, 2021, 5:37 AM

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ionic jewel a+b = 5+3?

ez

ionic jewel Jul 12, 2021, 5:37 AM

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use a and b as the names for the blanks in the left i guess

dim vector Jul 12, 2021, 5:37 AM

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Ohhhh tysm!!!

ionic jewel Jul 12, 2021, 5:37 AM

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i don't think you can assume this

dim vector Jul 12, 2021, 5:38 AM

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thanks for the explanation

tough hatch Jul 12, 2021, 5:38 AM

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dim vector Create the equation that corresponds to the following graph, use the letters a a...

also this is a diagram, not a graph. unless...

dim vector Jul 12, 2021, 5:40 AM

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tough hatch also this is a diagram, not a graph. unless...

I did not know, thanks for the information

hot oak Jul 12, 2021, 6:19 AM

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law of sines

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answers only pls i need it

ionic jewel Jul 12, 2021, 6:20 AM

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hot oak answers only pls i need it

... why only answers

hot oak Jul 12, 2021, 6:21 AM

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ionic jewel ... why only answers

my brain cant keep up

ionic jewel Jul 12, 2021, 6:21 AM

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well no one is going to give you answers, you already know it's law of sines, so you should go research that on your time first

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you have as long as you need

vast bobcat Jul 12, 2021, 6:24 AM

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ping when you answer, thanks ❤️

alpine sable Jul 12, 2021, 6:47 AM

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vast bobcat ping when you answer, thanks ❤️

try drawing it

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then you will find it out eventually

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that's all

vast bobcat Jul 12, 2021, 6:48 AM

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I've tried drawing but I can't figure it out

alpine sable Jul 12, 2021, 6:49 AM

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use vocabulary.com to understand each word

vast bobcat Jul 12, 2021, 6:51 AM

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is this right

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alpine sable Jul 12, 2021, 7:01 AM

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yes

left kite Jul 12, 2021, 7:07 AM

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can u help me pls

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for 6 c

dawn wraith Jul 12, 2021, 7:10 AM

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You have X and Y, just plug them in and solve for the tangent

echo python Jul 12, 2021, 7:10 AM

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say I have coordinates x and y as (0, 0), angle as 150 degrees and distance as 30, how would I calculate the new coordinates?

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basically drawing a line to the edge of the circle

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based on an angle

dawn wraith Jul 12, 2021, 7:12 AM

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What is that notation, is the angle of the rectangle 30 degrees?!

echo python Jul 12, 2021, 7:13 AM

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it's just a bad example so it's easier to understand what I'm trying to do

dawn wraith Jul 12, 2021, 7:13 AM

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I have no idea on how to help you out pal, I can’t visualise this issue..

thick flame Jul 12, 2021, 7:14 AM

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I think i may understand

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are you asking how to find the coordinates of a point 30 units away from the origin at an angle of 150 degrees from the x-axis?

echo python Jul 12, 2021, 7:15 AM

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kind of

dawn wraith Jul 12, 2021, 7:15 AM

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If that is so, then it may be possible.

thick flame Jul 12, 2021, 7:15 AM

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may be?

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of course it's possible!

dawn wraith Jul 12, 2021, 7:15 AM

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There are two possibilities.

thick flame Jul 12, 2021, 7:15 AM

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simple trig

dawn wraith Jul 12, 2021, 7:15 AM

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Yeah, trig.

echo python Jul 12, 2021, 7:16 AM

#

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if this is easier to understand

thick flame Jul 12, 2021, 7:16 AM

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?

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who made that image?

echo python Jul 12, 2021, 7:16 AM

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me in paint.net defective

thick flame Jul 12, 2021, 7:16 AM

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yeah, I get the feeling you don't understand the question

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from the information given I have a guess as to what the question is

echo python Jul 12, 2021, 7:17 AM

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I'm the one who has the question, I'm not doing exercises or something like that

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am working on a video game from the ground up without engine

thick flame Jul 12, 2021, 7:18 AM

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hmm

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and you

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are uhh

dawn wraith Jul 12, 2021, 7:18 AM

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Use the distance formula:
$$ d = \sqrt{(x2-x1)^2+(y2-y1)^2}$$

ocean sealBOT Jul 12, 2021, 7:18 AM

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Hunnydrips

echo python Jul 12, 2021, 7:18 AM

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and I want the x, y, z coordinates to be relative to the current pitch or whatever of the player

rigid smelt Jul 12, 2021, 7:18 AM

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or just use trig?

dawn wraith Jul 12, 2021, 7:18 AM

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Oh wait, at an angle of 150 degrees, then trigonometry should do the trick.

rigid smelt Jul 12, 2021, 7:19 AM

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you have a right triangle with a hypotenuse and angle given

echo python Jul 12, 2021, 7:19 AM

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I never had trigonometry at school, so that's kind of why I'm asking it here

rigid smelt Jul 12, 2021, 7:19 AM

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you can check it out online?

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in this case, you only need like a few formulas

echo python Jul 12, 2021, 7:19 AM

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I did search it but I couldn't find a way to solve it

dawn wraith Jul 12, 2021, 7:20 AM

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If you weren’t taught trigonometry, then why would you try to solve the issue with trig?

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I mean, you aren’t supposed to use it right?

rigid smelt Jul 12, 2021, 7:20 AM

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its not a math problem anymore

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they have said it

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i mean technically a math problem in general

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but not a school work

thick flame Jul 12, 2021, 7:21 AM

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does this describe your problem?

echo python Jul 12, 2021, 7:21 AM

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yes, exactly

thick flame Jul 12, 2021, 7:21 AM

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cool

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so there's an interesting thing where the point 150 degrees on the unit circle is (cos(150), sin(150))

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this works for all angles

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you can scale the values up by a value of 30 to get the position 30 units away at the same angle

dawn wraith Jul 12, 2021, 7:22 AM

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Were you taught of the unit circle?

thick flame Jul 12, 2021, 7:23 AM

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assuming no, since you don't know how to do this, the unit circle is just a circle of radius 1 centered at (0, 0)

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meaning all points on the circle are exactly 1 unit away from the origin

echo python Jul 12, 2021, 7:24 AM

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yeah

delicate spruce Jul 12, 2021, 7:31 AM

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how did the percentage turn into 1.08?

vale wigeon Jul 12, 2021, 7:42 AM

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@delicate spruce each year, the investment grows by 0.08 of itself

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i.e. each year it goes from some value x to x + 0.08x

delicate spruce Jul 12, 2021, 7:46 AM

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oh now i get it

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thanks

dim vector Jul 12, 2021, 7:49 AM

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someone know how to do this, easy way eeveeThink

upper pebble Jul 12, 2021, 7:49 AM

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what is Tu

dim vector Jul 12, 2021, 7:51 AM

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upper pebble what is Tu

It means that need an answer