#precalculus

1 messages · Page 125 of 1

sleek path
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Cant seem to do this at all

patent beacon
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There's three forces on the mass. The tension in each rope, and gravity. These forces should sum to zero

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If you're comfortable with component notation:
A[cos(30), sin(30)]

  • B[cos(135), sin(135)]
  • [0, -20g]
    = 0
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Gives two equations and two unknowns

sleek path
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are A and B the tensions?

patent beacon
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Yes! Forgot to mention

sleek path
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ok ok. How did you get to cos and sin

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is that just the x and y components?>?

patent beacon
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Yeah, that's the components of each of the vectors

sleek path
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wouldnt it be B[cos(45), sin(45)] then? or why are you using 135 instead of 45

patent beacon
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Because if you take the angle from the x-axis, then vectors always split in terms of [cos(), sin()]

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You should probably draw the diagram and split them the way you like

sleek path
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ohh the 135 is the exterior angle? got it

patent beacon
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But that's the procedure. Split the vectors, add them componentwise to get two equations

sleek path
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ok

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thank you so much for helping

patent beacon
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Np. Feel free to ask if you have anything else!

hearty plinth
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Hey guys I need help for this

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Find the std.eq of all circles having center at a focus of 21x^2-4y^2+84x-24y=36 and passing through the further vertex

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And

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Find the std.eqn of the hyperbola of which has focus and vertex that are the same as these of x^2-6x+8y=23 and whose conjugate axis is on the directrix of the same parabola

viscid thistle
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Just complete the square on the first one?

finite jolt
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can someone help me with 11? please

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<@&286206848099549185>

sullen shoal
stark violet
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<@&286206848099549185>

elfin night
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hmm

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Gotta post a q m9

thick raptor
sullen shoal
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Fucking hell

half ridge
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anyone here?

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I have an urgent question

fallen cloud
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ask it

half ridge
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use absolute value to describe the interval [2,8]
I know the answer is |x-5| < or = 3

gritty blaze
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And ?

cedar chasm
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when u find the domain of a rational function and like put numbers in to see if its positive or negative

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do u use the simplifed version you get by cancelling out terms

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or the original equation

viscid thistle
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Forty-five percent of a radioactive substance decays in four years.

By what percent does the substance decay each year?

Round your final answer to two decimal places.

mental trench
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Wouldnt you use a a decay formula? The whole A(1-r)^t

viscid thistle
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yeah but im lost about the specific one year part per 4 years @mental trench

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The amount of radioactive substance as a function of time in years is an exponential function of the form y=ab^t . Use this formula and the fact that after 4 years only 55% remains to find the growth factor b. The growth factor can then be used to find the annual percent growth rate, or growth factor, which will be negative as the substance is decaying.

mental trench
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And youre given no principle amount?

viscid thistle
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yep no initial value

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it is only based off of the percentages and times

mental trench
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Okay, i tried it and i got 0.86 which is 86 percent but that sounds extremely sus.

viscid thistle
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it still displays as incorrect lol. very odd

graceful egret
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<@&286206848099549185>

viscid thistle
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@graceful egret

graceful egret
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what

viscid thistle
graceful egret
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i might have posted my question in the wrong section so here it is again

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<@&286206848099549185>

viscid thistle
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Where did the 8 come from at the bottom of this?

bitter nova
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counting to 8

viscid thistle
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Counting what though?

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Thanks btw.

bitter nova
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kinda like a clock

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counting pi/6 angles from 0

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tbh it's pretty strange

viscid thistle
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Oh okay. Thanks a lot.

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I don't know how I didn't get that but that makes sense thank you.

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Does that only work in that quadrant? Because if I do 150 degrees I get 6pi/6 not 5pi/6

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Ignore that.. figured it out.

rocky bison
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240 = 8*30

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So there's 8 intervals of 30

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and 30º is pi/6 radians

viscid thistle
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When determining the period of -sin((x/2)+(pi/4)+5 why does x/2 = 1/2?

solar abyss
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=tex -sin(\frac{x}{2} + 5) + 5

granite stirrupBOT
solar abyss
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the period is

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=tex \frac{2pi}{b}

granite stirrupBOT
solar abyss
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=tex \frac{2\pi}{b}

granite stirrupBOT
solar abyss
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where b is the coefficient in front of the x in the sin

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so for that function the period is

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\tex = 4\pi

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$$ 4\pi $$

granite stirrupBOT
forest prawn
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Hi all, I’m having trouble with factoring out a function in order to find it’s zeros.

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I’ve tried the rational root theorem with synthetic division, as well as factoring out via grouping

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I’m wondering if I’m just missing something, or if I am doing something fundamentally wrong

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Also, as far as I know regarding the rest of the question, (Please correct me if I am wrong) it is an odd function as f(-x) = -f(x), it’s end behavior is positive approaching Inf. and -Inf, it is to the sixth (sextic) degree with a leading coefficient of 1.

patent beacon
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@forest prawn
It is not odd. Odd polynomials only have odd exponents. This is a neither.

End behavior is ∞, but since the degree is even, the "start" behavior is -∞.

You're correct about the degree and leading coefficients

forest prawn
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Thank you for pointing that out, not sure how I forgot how to find an odd/neither/even function

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Regarding the second point, that is due to the fact that, as the line comes in from the left, it is sloping downward causing it to be -Inf?

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Lastly, could you give me a starting point for factoring out the polynomial so that I can get off the ground with that? I feel like I have exhausted every option that I know

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I appreciate the help.

patent beacon
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= pup roots of x^6 - 5x^5 - 5x^4 - 45x^3 - 108x

granite stirrupBOT
patent beacon
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Not sure how you're supposed to find these

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Sorry, I misstated, the "start behavior" is ∞. It's on the same side because the degree is even

forest prawn
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Hmm, might have to bring this up to the teacher. He hasn’t officially handed this out, but I just happened to check the website and saw it was there so I figured I would take a crack at it.

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Just to clear it up, End behavior as x approaches -Inf can be found by starting at 0 and going left correct?

patent beacon
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Agreed, those aren't zeros you can find. Run it by him!

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= pup graph y = x^6 - 5x^5 - 5x^4 - 45x^3 - 108x

granite stirrupBOT
viscid thistle
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I don't understand this. There are no videos to help me.

patent beacon
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cos(a + b) = cos(a)cos(b) - sin(a)sin(b)

viscid thistle
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Oh, hold up.

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How would I get the cos(a) though?

vale pewter
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using the first identity you learn in trigonometry?

north bough
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can someone help me with this proof?

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=tex \frac{sin\left(x\right)}{1-cot\left(x\right)}+\frac{cos\left(x\right)}{1-tan\left(x\right)}=sin\left(x\right)+cos\left(x\right)

granite stirrupBOT
north bough
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I can't solve by doing something like subtracting cos(x) from both sides

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I already tried multiplying the part with sin(x) in the numerator by sin(x)/sin(x) and the part with cos(x) in the numerator by cos(x)/cos(x)

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I have also tried multiplying them by the conjugate of the expression on the right hand of the equation

viscid thistle
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about rectangular hyperbola
(proving y=1/x is a hyperbola)

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the fourth equation, i have no idea where the square root of 2 came from

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even how the y-x appeared there

spring thunder
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$$\left(\frac{x+y}{2}\right)^2 - \left(\frac{x-y}{2}\right)^2 = 2\frac{\left(\frac{x+y}{2}\right)^2}{2}+2\frac{\left(\frac{x-y}{2}\right)^2}{2}$$

granite stirrupBOT
spring thunder
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$$\left(\frac{x+y}{2}\right)^2 - \left(\frac{x-y}{2}\right)^2 = \sqrt{2}^2\frac{\left(\frac{x+y}{2}\right)^2}{2}+\sqrt{2}^2\frac{\left(\frac{x-y}{2}\right)^2}{2}$$

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$$\left(\frac{x+y}{2}\right)^2 - \left(\frac{x-y}{2}\right)^2 = \sqrt{2}^2\frac{\left(\frac{x+y}{2}\right)^2}{2}+\sqrt{2}^2\frac{\left(\frac{x-y}{2}\right)^2}{2}$$

granite stirrupBOT
spring thunder
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:O shuts

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(Fking internet)

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$$\left(\frac{x+y}{2}\right)^2 - \left(\frac{x-y}{2}\right)^2 = \frac{\left(\sqrt{2}\frac{x+y}{2}\right)^2}{2}+\frac{\left(\sqrt{2}\frac{x-y}{2}\right)^2}{2}$$

granite stirrupBOT
spring thunder
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$$\left(\frac{x+y}{2}\right)^2 - \left(\frac{x-y}{2}\right)^2 = \frac{\left(\frac{x+y}{\sqrt{2}}\right)^2}{2}+\frac{\left(\frac{x-y}{\sqrt{2}}\right)^2}{2}$$

granite stirrupBOT
tame plaza
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hi friends ! can I ask for help with understanding this...I'm not sure what you call it

spring thunder
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And (a-b)^2=(b-a)^2 for all a,b anyway @exotic path

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@tame plaza ya just ask

tame plaza
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should I ask here or in the questions

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;o?

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@spring thunder

spring thunder
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(Let it here : my internet is shit tho ATM)

tame plaza
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ah, im not sure if you can see it

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it's a file haha

fickle moat
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can someone explain to me x^2 = +,- i

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if your finding all zero's

rocky bison
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What do you mean @fickle moat

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=tex \pm i

granite stirrupBOT
fickle moat
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yes

rocky bison
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Can you give full context please?

fickle moat
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ok one moment

rocky bison
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Are you trying to find all of the imaginary roots of a quadratic?

fickle moat
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let me take a picture

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i get every answer EXCEPT x^2 = 0

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the answer from book says +,- i

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how????

rocky bison
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I can't read your question

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just post the original polynomial plz

fickle moat
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2x^5 -11x^4 +12x^3 -3x^2 +10x +8

rocky bison
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oof

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large degree

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Ok

limber bone
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hehe xd

rocky bison
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What did you do to try factor it

fallen cloud
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omgr....

limber bone
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gl bois

fickle moat
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i used syntheic division

fallen cloud
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synthetic, yep i learned it and then forgot it, never used it since

fickle moat
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now after doing that i gotten 2x^3 +x^2 +2x+1

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grouping

fallen cloud
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well... lets multiply that out to check if thats correct

rocky bison
fickle moat
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x^ (2x+1) (2x+1

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so x = -1/2 and x^2

rocky bison
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Well for a start your polynomial

fickle moat
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but x^2 =0 HOW is it =,- i

rocky bison
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has a constant on the outside

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So there should be no x^2 isolated

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Because that means all terms have a common factor

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which they don't

fickle moat
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i factored out x^2 from grouping

rocky bison
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ok I'm lost

fickle moat
rocky bison
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but in order to get pm i

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it should be (x+1)^2

fickle moat
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can you just explain to me how do you get X^2 = 0 is +.- i

rocky bison
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You don't

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x^2=0 doesn't have solutions pm i

fallen cloud
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i think something happened with the synthetic division

rocky bison
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It's x^2+1

fickle moat
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the professor says x =0 is wrong answer

fallen cloud
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i works

rocky bison
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that has sqrt -i and +i

fickle moat
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the answer is +,- i

rocky bison
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It is

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Clearly

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But in order to get x=i, x=-i

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You have to have x^2+1 as a factor

fickle moat
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i get it when you have x^2 = -1 you get x = +,- i

rocky bison
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yes

fickle moat
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but how the heck x^2 =0 gets +,- i

rocky bison
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It doesn't

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x^2=0 is wrong

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You've done something wrong to get to that

fickle moat
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give me a sec

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let me retake the picture

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@rocky bison

rocky bison
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I'm not familiar with synthetic division so I won't be helpful

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I thought you were just doing standard division with some extra information

fickle moat
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i got a 91 on test but i want to know where did that +,- i come from

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so is there any helper could help out ?

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@rocky bison

rocky bison
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Probably

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<@&286206848099549185>

dapper oar
fickle moat
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my hole point of question is x^2 = 0 it says +,- i

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i get where i missed

dapper oar
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wdym

fickle moat
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ok so u got 2x^3+x^2

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u factor x^2

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u get 2x+1

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i get you will get x = -1/2

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but for x^2

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how is it +,- i

dapper oar
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how have you got 2x^3+x^2

fickle moat
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you group

dapper oar
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what do you group

fickle moat
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oh my god

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do the grouping

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insteed factoring that

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insteed factoring out i grouped so i can factor out easier

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(2x^3+x2) (2x+1)

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now you can factor out x^2 for 2x^3+2

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x^2 ( 2x+1)(2x+1)

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now you solve that for all zero

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u get x = -1/2

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but MY QUESTION HERE is x^2 = +,- i

dapper oar
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No
2x^3 + 1x^2 + 2x + 1 does not equal (2x^3+x^2) (2x+1)

fickle moat
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ITS GROUPING

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can you factor x^2?

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for 2x^3 + x^2

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or not

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so what is it

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2x+1

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x = -1/2

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but xlfjaskldfjweri gki

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sorry frustration is rela

dapper oar
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you keep saying ITS GROUPING, but this is where you're making the mistake

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there is no factor of x^2

fickle moat
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without grouping

dapper oar
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I don't know what you mean by "grouping", but let me grab a pen and paper

fickle moat
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ok so insteed using quadratic formula

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i am spliting that each side

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so i can find all acution zeros

dapper oar
fickle moat
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2x^3+x^2+2x+1 same thing what i mean as group is ( 2x^3+x^2 ) ( 2x+1 ) l for 2x^3+x^2 what can you factor out?

dapper oar
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Sorry for the bad lighting, but does this make sense?

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specifically the second line

fickle moat
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yes

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3rd line is going to be

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x^2 (2x+1) (2x+1)

dapper oar
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No, you've gotten rid of the + sign again

fickle moat
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the plus sign goes inside (

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i did not miss the sign

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ok one sec

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let me retake pic

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if you solve that you will get orginal equation x^3

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i found all the x of real zeros

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but X^2

dapper oar
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you did miss out the sign

fickle moat
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......

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my question is X^2

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x^2 =0 HOW do you get x +.- i

dapper oar
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You don't, because you don't get x^2 = 0

fickle moat
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please thats all i really want to know

dapper oar
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Because if you don't miss out the sign, you get a different equation to solve

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x^2 = 0 does not give you x = +/- i

fickle moat
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so your saying x^2+1?

dapper oar
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Yes

fickle moat
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because me missing that + sign infront

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x^2+1 =0

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?

dapper oar
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it's not a "sign" in the same way that you have positive and negative signs, it's an operation, it's addition

fickle moat
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x^2 +1 = 0 => x^2 = -1 => x^2 root both side => x= root -1 ?

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x= +.- i?

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@dapper oar

forest prawn
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@fickle moat

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if you have (x^2+1)

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you can set x^2 = -1

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square root both sides and you get x = sqrt(-1)

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which is equal to i

fickle moat
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oh

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ok now i see where my teacher got +.- i from

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thank you

forest prawn
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no problem

neon vale
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please help

patent beacon
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What are they doing to x³ - 9?

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Or - what does h(x) do to x³ - 9?

neon vale
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6th rooted lol idk

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is it just 6sqrt x

patent beacon
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Exactly. So this is a 6th root that's been "applied onto" x³ - 9. The outer function is - that yes

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6th root of x

neon vale
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wow thanks that was easier than i thought how embarrassing lol

violet latch
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is anyone here at the moment?

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I need help with a max/min kind of problem

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quadratic equation

viscid thistle
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Can someone tel me the domain and range of -3(x - 3)^2 + 9?

hexed ermine
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What do you know about the domain and range for a standard quadratic

forest prawn
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@viscid thistle If vertex form is y=m(x-h)^2 + k, your vertex is (h,k).

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Your domain is = to all the values of x that your graph can possibly touch, with range being all values of y.

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You can use the rest of your knowledge about graphing functions to determine the domain and range fairly simply as long as you know the vertex

clear coral
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Does anyone know how to do 5 and 8

hexed ermine
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Use log rule

clear coral
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change of base?

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but how

hexed ermine
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loga^b = bloga

clear coral
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i still don't get how to use it in the context of first problem tho

hexed ermine
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log_9(5^log_5(27))

clear coral
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yeah still no clue

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the only exponent i see to bring down is a 3 from the 27 or 3^3

hexed ermine
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Look at the 5

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What do you know about 5^log(5)

clear coral
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huh I'm reading it as (log base 9 of 5 ) * (log base 5 of 27)

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I can't see where you're bringing down an exponent

hexed ermine
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Yes

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log(a)*log(b) = log(a^log(b))

clear coral
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Is it the same thing as that integer coefficient thing I'm used to but just with a log instead?

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so x = 3/2

hexed ermine
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Yes

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log_9(27)=1.5

clear coral
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and 8?

hexed ermine
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Isolate 8^2x

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Log both sides

clear coral
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eh?

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how

hexed ermine
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I dont feel like explaining , I'm sorry, someone else can help you

clear coral
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lol okay

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I don't feel like doing this either

hexed ermine
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With these types of problems I have to use paper bc it's hard keeping track of everything

viscid thistle
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@clear coral whats the question?

clear coral
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number 8

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scroll up

viscid thistle
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using ln/log?

clear coral
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ehhhh ummm idk how to isolate the 8^(x)

viscid thistle
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u can always ln it

clear coral
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yes but howww

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Idk how ln it

viscid thistle
clear coral
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I understand the power rule but there are no logs in this question

viscid thistle
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in order to solve these questions, u needa ln everything

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and solve from there

clear coral
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could you try explaining it in the context of the problem

viscid thistle
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would u like me to write it out?

clear coral
#

yeah

viscid thistle
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@clear coral

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im not that familiar with the rest... but does it help a little?

clear coral
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yeah it does '

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thanks much

viscid thistle
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lol i would like to know how to solve it too 😛

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do u mind posting ur results in the end?

clear coral
#

ooooooh okaaayyy I can tryyy

viscid thistle
#

lololol we are all in the same boat...

hexed ermine
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You cant combine the second part

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3^3*2^3x

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That doesn't equal 6^9x

clear coral
#

I knew it

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I just got there and got so confused

viscid thistle
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@hexed ermine wait.... isnt that like an exponent rule?

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oh no... nvm

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sorry... 😦

viscid thistle
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can someone message me if they are good with TVM solver or finance math (compounding stuff etc)

drifting hollow
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The most you can simplify 3^3 * 2^3x would be either 27*2^3x or 27 * 8^x

dense zealot
#

smh

viscid thistle
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hi guys

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whats the multiplicative inverse of 2+9i

patent beacon
#

1 / (2 + 9i)

viscid thistle
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k thx

patent beacon
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Np here for ya

atomic harness
#

i am stuck on number 3

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u know how to do that

viscid thistle
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@viscid thistle normally you would want to take the imaginary part out of the denominator if you want to represent it in general complex number form.

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U can do that by multiplying both nunerater and denominator by conjugate of the denominator

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Similar to how u rationalise denominators when u have irrational numbers as denominators

viscid thistle
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Yeah

sterile portal
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$$8/(2+h) $$

granite stirrupBOT
sterile portal
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Could I do 8/2 and get 4 and then have 8/h still or is that against the maffs rules

civic plaza
#

that is not valid

sterile portal
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👍Thanks

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I'm trying to find the slope of the tangent but I need an H variable in the answer for the slope of the secantthonker

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I tried getting rid of the fraction by just multiplying the denominator but I guess its not right

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Ping me please & thank you :)

severe verge
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rawrr

sterile portal
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I need helps I've been stumped

severe verge
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hmmmm

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(f(2+h)-f(2))/(2+h-2)

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(8/(2+h) - 8/2)/h

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(8/(2+h) - 4(2+h)/(2+h))/h

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(8-8-4h)/h

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-4

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seems legit

sterile portal
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But then what would the slope of my tangent be

severe verge
#

-4

sterile portal
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That was for the secant

severe verge
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but all the secants are -4

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and tangent is basically a secant but one of the good ones

sterile portal
#

And for the tangent u have a limit of H approaching 0

severe verge
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lim_{h→0} of -4 = -4

sterile portal
#

Oop

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Ur right lool

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The answer says it's - 2 but I guess typo?

severe verge
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ya prob

sterile portal
#

Ok thanks👍👍

severe verge
#

np

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maybe I am just dumb qthonk

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=wolf f(x)=8/x, f'(2)

sterile portal
#

My textbook got lots of error cause it's old and needs to be revised tbh lol

granite stirrupBOT
severe verge
#

oof

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where did we go wrong

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what the heck

sterile portal
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Idek

severe verge
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I am bamboozled

sterile portal
#

Wooaahh woog bamboozled?!!?

severe verge
#

lol

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ok now I will thonk

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about where we could have possibly gone wrong

thick raptor
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tl;dr you forgot the 2+h in the denominator

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which divides the result by 2

sterile portal
#

Thanks guysss now I feel stupid cause it wasn't that complicated

vapid oxide
#

how do i convert this into polar? 4x^2+3y^2-2y-1=0

i brick myself with some nonsense fraction expression that isnt the same graph

somber plaza
#

It’s a circle graph imao

vapid oxide
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yes i get that but i brick when i try to convert to polar

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:/

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can someone help me :?

civic plaza
#

use the substitutions: x=rcos(theta), y=rsin(theta)

fallen cloud
#

4xx + 3yy - 2y -1 = 0,

#

0 = rrcos(theta)cos(theta) -2rsin(theta)-1,

#

solve for r

#

r = (2sin(theta) +- 2)/(2cos(theta)cos(theta))

#

r = (sin(theta) +- 1) / (2cos^2(theta))

#

wait...

#

i think i did something wrong

#

yep, i forgot the + 3...

#

or something like that

vapid oxide
#

i always have a r left over on the other side for some reason D:

#

thats what i meant by brick

desert jackal
#

can someone explain compound interest y = ae ^bx to me

patent beacon
#

Have an example question?

desert jackal
#

you invest 100$ at 6% per annum compounded quarterly. how long will it take for balance to exceed 120$?

patent beacon
#

You want to find interest per compound. Banks are lazy af and they just decide that 6%/4 = 1.5% per quarter

desert jackal
#

would you use equation A=P(1+r/n)^nt

patent beacon
#

Yeah, you would!

desert jackal
#

ok

patent beacon
#

120 = 100(1 + 0.015)^(4t)

#

Make sense how I got there?

desert jackal
#

yeah

#

thank you

patent beacon
#

Ok. Feel free to ask if you have anything else!

vapid oxide
#

can anyone help me convert this into polar? 4x^2+3y^2-2y-1=0

i keep ending up with an r on the other side that i cant get rid of :/

viscid thistle
#

why do people not use questions chat

#

understandable

vapid oxide
#

actually nvm i finally found out why i bricked

thick summit
#

I need hand simplifiying a really weird question:
x^-(3a+7b)-8(-a-b) / x^a-5b
Never dealt with a question before that had more then a single number as the exponent, so I'm rather confused.

#

and sorry if I should be asking this elsewhere, I tried using a question channel but my message wasn't sent for some reason.

thick summit
#

<@&286206848099549185>

viscid thistle
#

Uhm could you specify? @thick summit

thick summit
#

Like the equation or what I need done with it?

#

e.e

#

I just need to simply x to the power of -(3a+7b)-8(-a-b) divided by x to the power of a-5b.

thick summit
#

Anyone?

hexed ermine
#

Same base

#

And its dividing

#

What do you do with the exponents?

thick summit
#

Simplify somehow?

bleak fractal
#

could someone help me with a complex number question?

#

why do they say that (z+6)^8=81 is the same as z^8=81??

#

wouldnt the +6 offset the answer

spring thunder
#

we're translating the triangle, but there's no rescaling : the area will be the same @bleak fractal

bleak fractal
#

that makes sense, thx!

spring thunder
#

👌

vapid oxide
#

can someone show me the work for this :/
(convert to polar)

4x^2+3y^2-2y-1=0

calm whale
#

ah

vapid oxide
#

converting to polar my b

#

i always brick it and i dont get the right answer

patent beacon
#

4x² + 3y² - 2y - 1 = 0

x² + 3(x² + y²) - 2y - 1 = 0

r²cos²θ + 3r² - 2rsinθ - 1 = 0

vapid oxide
#

yea i get that but i brick afterwards

patent beacon
#

Well, I'm done. That's a polar form.

#

Solved for r?

vapid oxide
#

yes

#

r= ?

patent beacon
#

(cos²θ + 3)r² + (-2sinθ)r - 1 = 0
Any easier?

vapid oxide
#

:/

calm whale
#

ax^2+bx+c=0 ..

patent beacon
#

This is a quadratic in r. Know the quadratic formula?

vapid oxide
#

yes

#

OH

#

i get it now

#

i never thought about using quadratic formula LOL

patent beacon
#

Lel. Think you've got it from here?

vapid oxide
#

yea now i got it

#

thanks so much 😄

#

aighty poggers

#

finally got it

#

r=(2sintheta+4)/(2cos^2theta+6)

fickle moat
#

So the equation for this problem i have is
A = 1500e^(.02 x 10)
And i plugged into calculator it only showa same number

Can someone tell me where did mess it up?

fallen cloud
#

you dont have a variable

calm thicket
#

== 1500e^(0.210)

granite stirrupBOT
#

1‚500×exp(2) = 11083.584148396

fallen cloud
#

it's a constant that you plugged in

#

unless 'e' is your variable

#

because 'e' is an actuall number, e = ~ 2.718281828

fickle moat
#

Oh

#

So e is for x

#

Is that what your saying or?

#

My english is pretty bad so..

fallen cloud
#

'e' should never be used as a variable

#

same with 'i'

viscid thistle
#

e and i represent numbers

rare zephyr
#

What was my mistake

#

<@&286206848099549185>

viscid thistle
#

=tex log_3(2x+5) - log_3(x) = log_3(\frac{2x+5}{x}) \neq log_3(\frac{x}{2x+5})

granite stirrupBOT
viscid thistle
#

And you forgot to flex.

rare zephyr
#

I'll try to keep forcing them muscles to flex itself

earnest finch
#

Yeah

viscid thistle
#

It's just a quiz.

earnest finch
#

Wow. Apparently it was a teacher's mistake. I actually got a 96% on that quiz. That's a bit better.

rocky girder
viscid thistle
#

look at the leading coefficient and the constant

somber plaza
#

@rocky girder look at rational root theorem

earnest finch
#

All the factors of the leading coefficient and the constant (last term)

viscid thistle
#

Yo guys I know the answers to this problem but I don't know how to get to them I'm looking for arc length, theta in radians and area of the section. This is a homework assignment.

faint acorn
#

Whats with the 7 and 12?

#

Oh I get it, its a clock

rancid ether
#

what does cos(arcsin(1/5)) equal to?

#

suppose to figure this out without calc

primal yarrow
#

Can you help me with a question?

#

It involves only high school Mathematics

#

@rancid ether

rancid ether
#

sure

primal yarrow
#

Sorry I am just really desperate

#

Let’s take this to dm then?

rancid ether
#

sure

hexed ermine
#

@rancid ether make a reference triangle with the given information

#

arcsin(1/5) indicates an angle value, we will call theta

#

with that, sin is opposite of hypotenuse

#

once you have that you can label the adjacent side of theta using the pythagorean theorem

#

once you do that you do adjacent over hypotenuse for that

somber plaza
#

@hexed ermine hes solved it already lol

#

i posted literally what u said earlier

viscid thistle
#

for a greatest integer function, ex. [2x-1], when do we know to stop graphing

chrome grove
#

Is this where I can ask about trigonometry?

frozen needle
#

yes

chrome grove
fickle moat
#

simplify the expression how do you do that

#

#25

#

can someone explain to me? or Do i have to write it in y = b^x? formet

#

<@&286206848099549185>

sullen shoal
#

1

limpid plover
#

1

fickle moat
#

how tho

sullen shoal
#

8^1=8

elfin night
#

👀

limpid plover
#

Let $$log_8 8=x$$

granite stirrupBOT
fickle moat
#

what about 27

sullen shoal
#

lol it's \log

limpid plover
#

$$8^x=8$$

granite stirrupBOT
fickle moat
#

hm....

limpid plover
#

I am 9000% sure that I put a slash there

fickle moat
#

what about #27

#

the answer says 0

#

but how though

sullen shoal
#

Well, fuck you!

limpid plover
#

$$log_n 1=0$$

granite stirrupBOT
sullen shoal
#

n^0=1

limpid plover
#

That's true for all n>0

sullen shoal
#

^

fickle moat
#

i get the concept but

#

7.5^1?

sullen shoal
#

7.5

fickle moat
#

what am i missing

limpid plover
#

And probably all n but log isn't defined for all n so eh

#

Let $$log_{7.5}1=x$$

granite stirrupBOT
sullen shoal
#

==65465467^0

granite stirrupBOT
#

1

limpid plover
#

$${7.5}^x=1$$

granite stirrupBOT
limpid plover
#

What's x

fickle moat
#

1?

sullen shoal
#

==7.5^1

granite stirrupBOT
#

15/2 = 7.5

fickle moat
#

wait

#

🤦

#

okok

#

now i see

#

;;;;;

#

@limpid plover thank you

sullen shoal
chrome grove
#

oof

fickle moat
thick raptor
fickle moat
#

oh...woop sorry

earnest finch
#

5log5 cancel out so you're literally left with 3 @fickle moat

sullen shoal
#

$$5^{\log_5(3)}$$ in log form is $$\log_5(x)=\log_5(3)$$

granite stirrupBOT
viscid thistle
#

what is an equation that will move the vertex of the function y=x^2 to the point (-3,1)

#

nvm i got it

sullen shoal
#

xd

limber bone
#

y = (x+3)^2 +1

chrome grove
#

can someone break that down or link me something that covers this?

odd lichen
#

It's mainly identities and rearranging.
Identities found through symmetries in the unit circle. Like sin(-x)=-sinx

#

Oh and similar and common triangles.

#

@chrome grove

viscid thistle
#

hi hi

#

can i please get some assistance

#

this is my work

#

i've gotten to the graph part but im confused on finding the intervals for this problem

#

can i please get some help 😃

#

the first point of the graph should start at (-5,0)

#

im only graphing for one period

#

so when trying to find the last point of the graph (where it ends), i did
-5+(-20/7)

#

since the period is (-20/7)

#

my last point should've been -55/7

#

BUT, when i checked desmos it was wrong

#

i didn't get (-55/7,0) like i should have

#

@patent beacon i know, it's all sorts of fucked up

#

lmao

hexed ermine
#

Indeed -55/7 is a zero

#

And it looks from what I graphed it's a zero

#

Perhaps yours is a bit messed up

viscid thistle
#

but why is it giving a weird fucked up number on desmos?

#

a scientific notation sort of number?

hexed ermine
#

Well that's a very small number close to 0

#

Idk why it didnt give you zero though

viscid thistle
#

yeah, that what im wondering as well

#

also

#

check this out

#

if i had done -5+(20/7)
i would've gotten a zero

#

-55/7 is also less than -5

#

so how does ur last interval is less than ur first

#

like this question is weird af

#

the period is negative

#

BUT

#

if it was positive

#

i would've gotten the end point for the graph

#

it doesn't make sense

hexed ermine
#

-5+(20/7)?

viscid thistle
#

-20/7 is your period right?

#

is that what u got?

#

cuz that's what i got

#

BUT

#

if the negative wasn't there

#

i would've gotten a flat 0

#

and the graph would've been right

#

but since the period=(-20/7), we are both getting -55/7

#

if -5 is our first point, then how is -55/7 gonna be our last point

hexed ermine
#

-5-(20/7)?

viscid thistle
#

yes

#

that's what i did in order to find the last interval

#

but

#

it gives us a number less than -5

#

which shouldn't be right

#

we might need more peeps on this problem

#

lmao

#

im so confused with the intervals

hexed ermine
#

I'm not sure what you're asking

#

Why did you circle that value?

viscid thistle
#

can we talk about this in a vc, i feel like i can explain myself better

#

never mind, there is no vc's on this server

#

ok

#

which value are you referring to in which i circled?

hexed ermine
#

The circle after the -2

#

-5 is a zero so that means a zero will also be at +-20/7

viscid thistle
#

in the desmos graph?

#

that's the "last" interval

hexed ermine
#

So -5+(20/7) and -5-(20/7) which gi es you -15/7 and -55/7

viscid thistle
#

yes

#

-15/7 should be the last interval

#

BUT

#

since we are subtracting both numbers, we get -55/7

#

which is not a flat 0 for the y

hexed ermine
#

-55/7 =x gives you a 0 for y

viscid thistle
#

no it doesnt

hexed ermine
#

I know your shits fucked up

#

Trust me, it's a zero

viscid thistle
#

can i see ur graph

hexed ermine
#

==-55/7

granite stirrupBOT
#

-55/7 = -7.85714285714286

viscid thistle
#

now check this out

#

the last interval should be greater than -5

#

not less than -5

#

you see what's wrong tho right?

hexed ermine
#

Your period is just a magnitude, if you add 20/7 to -5 you get a value greater than -5

viscid thistle
#

yes

#

there should be no point less than -5

#

if my first point is gonna be -5

#

all points succeding should be >-5

hexed ermine
#

Why do you say that?

viscid thistle
#

because

#

the graph starts at (-5,0)

#

if im finding the period from there, then all the x values succeding should be >-5

#

so how is it that the last interval is <-5

#

that doesn't make sense

#

the graph doesn't go backwards

#

there's an order to these graphs. the last interval will never be less than the first interval. it doesn't make sense

#

the last interval should've been -55/7. i got that BUT, it's not giving a flat 0. it's giving me some fucked up scientific notation

#

also, -55/7 doesn't make sense because it's less than -5

hexed ermine
#

So you are saying that for a regular sin(x) graph, -2pi isnt valid

viscid thistle
#

im saying the graph shouldn't go backwards. that's what im confused about. why is it saying that the last interval is -55/7 when it gives me a scientific notation and it's less than the first interval

#

-2pi is valid

#

but since the amplitude and horizontal stretch are both negative, it reflects just as a regular sin graph should

#

they both cancel out

#

returning to it's natural form as if the negatives were not present

hexed ermine
#

The period is -20/7 so since you are saying -5 is the starting point you should go back to find the number after that since the period is negative

viscid thistle
#

im saying that the last interval shouldn't be -55/7

hexed ermine
#

Why not though?

viscid thistle
#

because it's not giving us a flat 0 as it should

#

desmos isn't fucking up, it's something with this equation

#

also, -55/7 is less than -5

#

which doesn't make sense

#

goow, what do u think

spring thunder
#

it's not giving a 0 cause floating arithmetic isn't accurate

viscid thistle
#

i don't get it

#

what's floating arithmetic

spring thunder
#

(And screw my internet)

viscid thistle
#

lmao

#

so ur saying that -55/7 is right?

spring thunder
#

The calculations with floating numbres

#

Yes

#

It's just that computers can't store infinite digits

#

So there's a small error

viscid thistle
#

Holy fuck...

#

Ur right

#

but im so confused

#

this is insane

spring thunder
#

trust your mind, not those computer scumbags

viscid thistle
#

but wait

#

ahh fuck this

#

im just gonna go off of -55/7

#

this question has fucked with my head too much

#

thanks for the help y'all

#

i appreciate it (:

hexed ermine
#

👌

spring thunder
#

🍻

odd knoll
#

I don’t know what phi symbol means

#

for number 131

#

it looks like theta but its wonky

bitter nova
#

it's the other 3d angle

odd knoll
#

huh

#

ive never seen that symbol before ;-;

bitter nova
#

yea it's just another greek letter for another angle

odd knoll
#

oh

#

so its just like

bitter nova
#

p h i

odd knoll
#

another variable

bitter nova
#

yea

odd knoll
#

wow

#

okay

#

then

#

welp that makes sense now thx xD

grizzled solstice
#

Guys I need help with my homework 🙏🙏

#

What is the polar form of this

gritty blaze
#

$$z=\sqrt{6}e^{i\arctan\left(\frac{\sqrt{2}}{2}\right)}$$.

granite stirrupBOT
grizzled solstice
#

Ahh thanks 🙏🙏

odd lichen
#

π/4 +2nπ >>> arctan(sqrt(2)/2)

somber plaza
#

@grizzled solstice think about a Pythagorean triangle.

#

The R in the polar form is the hypotenuse

#

So the angle must be the theta

grizzled solstice
#

I see . Thanks you very much 🙏😁 @somber plaza

somber plaza
#

But of course you may have to change the angle depending on which quadrant the point lies on in an Argand diagram .@grizzled solstice

grizzled solstice
#

I got it ! Thx again @somber plaza

subtle narwhal
#

how do i find the difference quotient for this

spring thunder
#

still need ahelp ? @subtle narwhal

vapid skiff
#

Where can I post trig questions?

spring thunder
#

here is pretty relevant

vapid skiff
vapid skiff
#

This is what I've got so far

somber plaza
#

@vapid skiff graph sin(x + 2π /3 ) first

#

then shrink that graph by a third vertically

subtle narwhal
#

@spring thunder yes

spring thunder
#

ok so you know what a difference quotient is at least?

subtle narwhal
#

yeah

#

f(x+h)-f(x) all over h

spring thunder
#

well here the variable seems to be t, but w/e

#

$$\frac{f(t+h)-f(t)}{h}$$

granite stirrupBOT
spring thunder
#

so f(t+h) blocks you i believe....

subtle narwhal
#

yes

#

and square root too

spring thunder
#

if i took a function like g : x -> 2x+3, what's g(t+h)?

#

or you just have no idea

subtle narwhal
spring thunder
#

i mean, i didn't tell you to use symbolab

subtle narwhal
#

i didnt use symbolab

#

i just use their bad

#

bar

#

so its easier

#

to write

spring thunder
#

ah k lel

subtle narwhal
#

i didnt actually calcualte it

spring thunder
#

i was like wtf

subtle narwhal
#

thats stupid whats the point of coming here then lol

spring thunder
#

so you did 2(x+h) + 3 right (ie 'replaced' that x with x+h)

#

so for $$h : x \mapsto \frac{1}{4x}$$

granite stirrupBOT
spring thunder
#

waht's h(t+h)?

#

(and screw my notations but just do it)

subtle narwhal
#

1/4t+4h

#

but how do i simplify it further?

patent beacon
#

Get a common denominator

spring thunder
#

put them at the same denominator and rationalize basically

vapid skiff
#

@somber plaza how would I do that?

solid reef
ruby hill
#

help D:

gleaming vine
#

?

ruby hill
#

i'm not good at writing functions from looking at a graph of sinusoidal function

gleaming vine
#

maybe this?

#

idk i just read the title

ruby hill
#

ahhh.

north bough
#

how do I write this as an algebraic expression not using trig functions?

#

=tex sin\left(cos^{-1}\left(x\right)+sin^{-1}\left(x\right)\right)

granite stirrupBOT
gritty blaze
#

$$\sin(a+b)=\sin(a)\cos(b)+\cos(a)\sin(b)$$.

granite stirrupBOT
north bough
#

I'm aware of the addition identity for sine, but how would you represent the inverse cosine and sine functions?

civic plaza
#

let a=cos^-1(x) and let b=sin^-1 (x)

rocky bison
#

exactly the same way

civic plaza
#

that should be easier to see

north bough
#

why can we arbitrarily do that?

civic plaza
#

what do you mean

#

we aren't doing anything

#

in the end a is still cos^-1(x) and b is still sin^-1 (x)

north bough
#

ok

#

can you represent the values in terms of ratios of x?

#

like sin B in this case would be x

gritty blaze
#

$$
\begin{aligned}
\sin(\arccos(x)+\arcsin(x)) &= \sin(\arccos(x))\cos(\arcsin(x))+\cos(\arccos(x))\sin(\arcsin(x)) \
&=\sqrt{1-\cos^2(\arccos(x))}\sqrt{1-\sin^2(\arcsin(x))} + x^2 \
&=1-x^2+x^2 \
&=1
\end{aligned}
$$.

granite stirrupBOT
desert jackal
#

@sour wolf

sour wolf
#

yes?

quartz bronze
#

I know where the mistakes were made but not how to show the correction algebraically.

fickle moat
#

I have a question for number 14 and 15, 18
For number 13
Log 3 35 then i know its log 3 5 + log 3 7
But for number 14 15 17¿? How do you solve it

spring thunder
#

@fickle moat yep so,

#

$$\log(ab) = \log(a)+\log(b)$$ right

granite stirrupBOT
fickle moat
#

yes

spring thunder
#

that's what you used for the first q

fickle moat
#

itf its fraction you -

#

ok so the 14 log 3 5/7 is log 3 5 - log3 7?

spring thunder
#

yea, do you get why we substract?

fickle moat
#

i wrote in equation here

#

but

#

lost bit

#

@spring thunder is it this correct?

#

something like this?

spring thunder
#

yea those are correct

fickle moat
#

so if then

#

log 3 5/7

#

log 3 5 - log 3 7?

spring thunder
#

yea i didn't say that was false

fickle moat
#

than for 18 log 3 45/49

#

its subtraction

#

but can i like divide by 9 and 7

#

log 3 5/7

#

log 3 5 - log 3 7

#

i am not sure even i am doing this correct

spring thunder
#

just go with the easier things first

#

(and yeah log_3(45/49) isn't log_3(5/7))

fickle moat
#

so the answer for 18 is log 3 5 -log 3 7

#

your just following the rules of properties and same time solving it

#

i just have so many doubting myself...

spring thunder
#

no?

#

$$\log_3(\frac{45}{49}) = \log_3{45} - \log_3{49}$$

granite stirrupBOT
spring thunder
#

see

#

let's just start from this

fickle moat
#

oh you dont solve it

#

ok

spring thunder
#

they just want to write that big log_3(45/49) with some log_3(5) and log_3(7), that's all they want

#

and i didn't say this had only one step

fickle moat
#

so in the end you can write this in any form of -

#

45 -49 and 5 -7

#

so for number 15. log 3 7/25 = log 3 7 -log 3 25

spring thunder
#

and 25 is 5^2

fickle moat
#

log 3 7 -log 3 5^2?

spring thunder
#

yup and then what can you do?

fickle moat
#

do you have to solve for ^2?

#

i dont understand by mean what can i do afterward

spring thunder
#

what do you even mean by solve?

#

it's not an equation

#

can you use a rule to get something*log_3(5) instead of that log_3(25)

#

that's what i mean

fickle moat
#

now next question i hve is log 3 175

spring thunder
#

we're not finished with that one

fickle moat
#

oh

#

um

spring thunder
#

$$\log(a^b) = b\log(a)$$ hmmm

granite stirrupBOT
fickle moat
#

log 3 7 - 2log 3 5?

spring thunder
#

yas^^

fickle moat
#

so for 16

#

log 3 175

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i will have to change that to

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log b x^power?

spring thunder
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yeah that's the idea

fickle moat
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and do the samething

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as 15

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175..hm...

spring thunder
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it will be a little bit more complicated than just log_b(x^some power) tho

fickle moat
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so

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for 175..

spring thunder
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do you know what prime factor decomposition is?

fickle moat
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no

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i might either forgotten or

spring thunder
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each integer > 1 can be uniquely decomposed as a product of prime factors

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and a way to find it to start by the smallest prime number existing (ie 2)

fickle moat
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so its like finding constand and LC

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constant"

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constand of 10 is 1 2 5 10

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etc

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CONSTANT""""

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175 / 5 = 35 / 5 =7

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5 x 5 x 7?

spring thunder
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yas

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ie 5^2 * 7

fickle moat
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so than log 3 5^ log 3 7

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2 log 3 5 log 3 7

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?

spring thunder
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you forgot the + between the two but yeah

fickle moat
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OOPs

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okok so i got the right idea

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i finished the homework but i wanted to get better at it for my exam next week

spring thunder
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👌 sure

fickle moat
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so far i studied 2.7 3.1 3.2 solving least 90 problems

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including word problems

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so i can understand the full chapter

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thank you!

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for this you need to use subtract

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to do that do you have to x power to cube to cancel the root along with 3?

spring thunder
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how would you write cubert(x) as a fractional exponent?

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that's the trick @fickle moat

fickle moat
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i solved it i think

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one moment

spring thunder
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yup that's the right step

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now 1/3 hmmm......

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$$\log(b \cdot \frac1{b}) = \log{1} = \mathbf{0 = \log{b}+\log{\frac{1}{b}}}$$

granite stirrupBOT
spring thunder
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ie log(1/b) = -log(b)

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or you can just rewrite 1/3 as a power of 3

tardy olive
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find all solutions to 3x - 2^x- 1 =0

thick raptor
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ez @tardy olive

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The two real solutions are trivially 1 and 3

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and you can show with basic calculus there are no other real solutions

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The general solutions can be given by the Lambert W function.

tardy olive
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uh how do we solve this without calculus

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@thick raptor