#help-0

1 messages · Page 752 of 1

candid thistle
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It's alright, everone starts somewhere

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I too

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I spent an entire day on one problem and still havne't finsihed :/

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Speaking of which i should work on that

leaden galleon
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Lol

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Good luck

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I’ll be back next time guys if I end up having questions with math again

candid thistle
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kk

leaden galleon
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Cya 🙂

last narwhal
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how to quickly find numbers that satisfy the equation

candid thistle
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Set all three of them to be equal

surreal meadow
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this looks like a 2010 olympiad problem

wind bane
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like, integer solutions? or just any old numbers

surreal meadow
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i'm sure there's a solution they provide

ocean sealBOT
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Eat water it's good

candid thistle
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If it allows simplest radical form.

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It is more likely that they are asking for integer solutions but idk ¯_(ツ)_/¯

last narwhal
wind bane
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would ask in the number theory channel

quick timber
alpine sable
ocean sealBOT
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Eat water it's good

candid thistle
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Another thing is, you should simplify 66/3.

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If <BAQ = <QAC (angle bisector), would r/t = s/u

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I see my drawing skills are improving :/

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rather, getting worse

heady tusk
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busy?

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you know I could do this but I'm soo tired and this is the last question

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so can I please get some help

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I really wanna go to sleep

candid thistle
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I don't speak that language

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Factor f(x)?

heady tusk
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oh ye

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mb

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you have to find/calculate the numeric values of a and b

candid thistle
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oh ok

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First off

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plug in -2 as x

heady tusk
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and in line 2 it says (x-1) is a factor of f(x)

candid thistle
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Is that german?

heady tusk
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1 sec

heady tusk
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some things are similar

candid thistle
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ok lol

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its not that hard to understand it after reading it 1-2 times

heady tusk
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but they already told us what f(-2) would give?

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it gives 9

candid thistle
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yes

heady tusk
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so why would I plug it in

ocean sealBOT
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Eat water it's good

heady tusk
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yes

candid thistle
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4a - 2b = ?

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2a - b = ?

heady tusk
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uhm

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wait

candid thistle
heady tusk
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19

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I think

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no

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28

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@candid thistle

candid thistle
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yea

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so 2a - b = 14, that means that a = what in terms of b

heady tusk
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28?

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oh it's 14?

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how

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oh half

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of 28

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nvm

candid thistle
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-19 + 4a - 2b = 9, 4a - 2b = 28, so 2a - b = 14

candid thistle
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But yeah, using this, what is a equal to in terms of b

heady tusk
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a=8

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b=4

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OK wait lemme write down what I got so far

candid thistle
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thats one possibility but you have to make sure that f(x) has a factor of (x - 1)

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also idk if you can guess

heady tusk
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it says

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x-1 is a factor of fx

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in the question

candid thistle
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I was just going to suggest isolating a, then writing f(x) without any a's and only b's

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yeah

heady tusk
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so that's it

ocean sealBOT
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Eat water it's good

native temple
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this active?

candid thistle
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but you cant really guess since a could be 100 and then b = 186

candid thistle
native temple
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I have this book….

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And it mentions place value

candid thistle
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as in for example in the number 14, the 1 represents 10 and 4 represents 4?

heady tusk
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@candid thistle so final answer is a=8 and b=4?

candid thistle
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not necessarily

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because (x - 1) has to be a factor

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and a could be anything

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for instance plug in a = 100, that would make b = 186

heady tusk
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but if (x-1) is a factor

ocean sealBOT
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Eat water it's good

native temple
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in this section it mentions place value

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what is that I forgot

heady tusk
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wouldn't it be correct in that proportions?

native temple
ocean sealBOT
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Eat water it's good

native temple
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you said it wasn’t active..

candid thistle
candid thistle
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Sorry :(

heady tusk
candid thistle
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Ahh

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how is that?

heady tusk
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oh wait

candid thistle
heady tusk
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should a be a be 4?

candid thistle
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?

heady tusk
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but the questions asks for a and b

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but it can be more than 1 thing?

native temple
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@candid thistle No water will slit theough your teeth also you don’t stick your tongue out when eating it’s dangerous and disgusting

candid thistle
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idk you need to have two values of a and b that satisfy that and when f(x) is factored, (x - 1) should be one of the terms

native temple
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sorry for starting small talk in here

candid thistle
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So you have to find those

heady tusk
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bruh it feels like I'm so close

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but oh so far

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lmao

candid thistle
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Yeah :/ I had that two days ago

alpine sable
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so

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i need some help as im going to the 8th grade in a american school, where i learnt most of my mathematics in a different language.

heady tusk
alpine sable
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whats the best video that could probably help me with mathematics 8th grade.

candid thistle
heady tusk
candid thistle
heady tusk
oak chasm
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@alpine sable Sorry, channel is busy. Try Khan Academy. Has video lessons on mathematics classes.

heady tusk
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@oak chasm yooo my man

candid thistle
heady tusk
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is there any way that you can help me with this question?

candid thistle
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I can't help from here as I suck at quadratics

oak chasm
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@heady tusk What's the question?

oak chasm
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f(x) = 2x³ + ax² + bx - 3
f(-2) = 9
(x - 1) is a factor

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So, if (x - 1) is a factor, then f(1) = 0.

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So, use the definition of f(x) to find f(1).

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What do you get?

heady tusk
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the definition of f(x)

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uhm

oak chasm
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Yeah, f(x) = 2x³ + ax² + bx - 3.

heady tusk
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you get

oak chasm
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Fill in 1 for x.

heady tusk
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0

oak chasm
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No, you don't.

heady tusk
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cus x-1 is a factor

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right?

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oops

oak chasm
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No, use the definition of f(x), not the fact about roots.

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You'll see why in a minute.

heady tusk
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ok

native temple
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this active?

heady tusk
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you get

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2+a+b-3

oak chasm
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@native temple Yes.

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Good, now simplify.

heady tusk
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a+b-1

oak chasm
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f(1) = a + b - 1

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f(1) = 0

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So, a + b - 1 = 0

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Does that make sense?

heady tusk
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yes

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so can I now cculate a and b?

oak chasm
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Find f(-2) according to the definition of f(x).

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Almost.

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You need two equations to find two variables.

heady tusk
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I found this already, can't we use this?

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yes cus that's another eqaution

oak chasm
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OK, good.

alpine sable
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Is that indices ;w;?

heady tusk
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OK I'll try now

oak chasm
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Now you have:
a + b = 1
2a - b = 14

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Solve the simultaneous equations.

heady tusk
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mhm

oak chasm
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,rccw

ocean sealBOT
oak chasm
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OK, what's b?

heady tusk
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uhm

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1 second

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-4?

oak chasm
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Right.

heady tusk
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if you sub it in

oak chasm
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Now check it with your original equation.

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Get f(x) with a and b filled in.

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Make sure that f(1) = 0 with that new formula.

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Make sure that f(-2) = 9 with that new formula.

heady tusk
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f(1) works

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lemme check the other one

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f(-2) also gives 9

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or wait

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does it

oak chasm
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Well, do the work on paper.

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Let's see.

heady tusk
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yay it works

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the equation is correct

oak chasm
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OK, so your answer is a = 5, b = -4.

heady tusk
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tysm again

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NOW I CAN SLEEP

oak chasm
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You're welcome.

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Have a good sleep

heady tusk
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you are amazing

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ahhh

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bye

oak chasm
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Bye

native temple
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mentions place value

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what is that I forgot

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and how does this work

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I don’t understand step 1

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I would continue

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but I forgot what place value is

oak chasm
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Is this for finding the remainder after division by 11?

native temple
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okay I guess I can show a few more pages

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IDK

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tbh

oak chasm
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OK, so the digit sum method gives you the remainder after division by 9. The digit difference method essentially gives you the remainder after division by 11, though with 10 handled strangely.

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You're asking how to do the digit difference method?

native temple
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Yea

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IDK how this works

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specifically

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Idk what place value is

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even odd “place value

oak chasm
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OK, so you number the places in the number, starting with the place left of the decimal point, like this:

Let's say your number is 1309.567.

1  3  0  9  .  5  6  7
4  3  2  1  .  0 -1 -2
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See how the second line starts numbering at 1, then goes to the left 2, 3, 4, 5, 6, 7, 8, 9, 10, etc, until you get to the start of the number?

native temple
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yes

oak chasm
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And just like going to the left increases by one each time, going to the right decreases by one each time, which is why we get 0, -1, -2, -3, -4, etc after the decimal point until the last digit of the number.

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So, now we add together the digits in the odd numbered places.

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1  *3*  0  *9*  .   5  *6*  7
4   3   2   1   .   0  -1  -2
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3 + 9 + 6 = 18

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See how I added the digits in the odd numbered positions?

native temple
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oh

oak chasm
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Then I add the even numbered digits:```
1 3 0 9 . 5 6 7
4 3 2 1 . 0 -1 -2

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1 + 0 + 5 + 7 = 13

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Then I subtract the even sum from the odd sum:
Odd sum - even sum = 18 - 13 = 5.

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Does that make sense?

buoyant scaffold
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Is this available

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Nobody answered me in the question-1 channel

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It's been like 25 mins

native temple
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okay

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I see

oak chasm
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@buoyant scaffold Sorry, you need to keep the question in one channel.

gaunt magnet
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<@&268886789983436800> i need to change my name

night geyser
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To?

gaunt magnet
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i cant change name

native temple
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so to get digit sum of $ 132197.192$

night geyser
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Yes, that's intentional

tall wing
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right this is by design

buoyant scaffold
gaunt magnet
night geyser
#

What do you want it changed to?

native temple
gaunt magnet
night geyser
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slightly aggressive

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but sure

gaunt magnet
#

ty

native temple
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so to get digit sum of $$ 132197.192$$

ocean sealBOT
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Nerdy_Coder

native temple
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what

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uhh

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$so to get digit sum of $ 132197.192$

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one line

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so to get digit sum of $ 132197.192$

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so to get digit sum of $ 132197.192 $

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there we go?

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why isn’t this working!

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so to get digit diffrence of $ 132197.192 $

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$ 132197.192 $

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$$ 132197.192 $$

ocean sealBOT
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Nerdy_Coder

native temple
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so to get digit difference of this number

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do

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$$ 1 + 2 + 9 + 1 + 2$$

ocean sealBOT
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Nerdy_Coder

native temple
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which is $$ 15 $$

ocean sealBOT
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Nerdy_Coder

native temple
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15 - 3 + 1 + 7 + 9

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which is 20

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the result is -5

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but this can’t be negative os ot’s negative 5 + 11

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which is 6 right?

native temple
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<@&286206848099549185>

hollow sage
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CAN SOMEONE HELP ME WITH THIS PLEASE

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ive been stuck on this for my entire life im now 91 years old and i can't figure it out ]

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<@&286206848099549185>

topaz scaffold
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You know what foil is?

hollow sage
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no?

topaz scaffold
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Oh

hollow sage
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oh like inner and outer

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and stuff

topaz scaffold
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Yea

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That's what you would use here

hollow sage
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oh yea

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thanks

wheat condor
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<@&286206848099549185>

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what’s the right answer

topaz scaffold
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0

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For both

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Since a tangent line would be flat ther

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There*

brittle wasp
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0 is a straight line :|

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Oh wait my bad

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Hey can someone help me out with this question pls?

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<@&286206848099549185>

topaz scaffold
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,rotate

ocean sealBOT
wheat condor
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thank u s much

topaz scaffold
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The planes seems parallel to each other

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So they wouldn't intersect

brittle wasp
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Thank you ripe@topaz scaffold

topaz scaffold
alpine sable
topaz scaffold
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Sum means add

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Spam protection lol

alpine sable
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wait what

topaz scaffold
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Sum of 1 and 2 means what do you get when you add 1 and 2 together

alpine sable
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what would i get catThink

glass lichen
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0

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in Z_3 at least

alpine sable
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okay thank you

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wait it says error

topaz scaffold
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Hopefully he/she didn't actually enter 0

alpine sable
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are you sure that’s right?

glass lichen
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yes

topaz scaffold
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Yes

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But

glass lichen
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Im positive 1+2=0 in Z_3

topaz scaffold
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1+2=10 in base 3

alpine sable
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okay i will try that, thank you!

topaz scaffold
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Are you actually unable to do addition?

alpine sable
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mf

wheat condor
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is someone near a pen and apper

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paper

topaz scaffold
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Depends what you define as "near"

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I gotta stand up and walk to get the pen so I would say no (?)

warped phoenix
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is this true?

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you can make the exponents of an equation into their own equation

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and then solve for x?

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instead of doing a log and getting the x out of the exponent area

topaz scaffold
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Well doing that is basically the same as doing log_2 on both sides

warped phoenix
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huh

topaz scaffold
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Kinda like saying 3 * x = 3 * y

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So just comparing x and y

warped phoenix
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so this can only be done if there's an x in both exponents of both sides of the equation?

topaz scaffold
#

x = y

topaz scaffold
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For example $2^x = 2^2 \implies x = 2$

ocean sealBOT
#

RipeOrange

warped phoenix
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ah

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for the function g(x) = f(1/3x), g(x) would have a horizontal stretch by a factor of 3, and if g(x) = f(3x), g(x) would have a horizontal compression by a factor of 1/3

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right?

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just to make sure ive got that correct

topaz scaffold
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Yep

warped phoenix
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great

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ty!!

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oooh one more thing

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ik something like this depends from person to person

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but ive got my alg 2 final tmrw

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what do you guys think would be most beneficial for review? taking the khan academy mastery course for alg 2 over and over until i stop getting questions wrong or simply watching a yt vid i found that goes over the entirety of the course of alg 2 (~3 hours)

topaz scaffold
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I didn't study for mine dead_inside

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Depends how confident you feel about the content ig

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If you feel good about it you could probably just review the concepts that you're not as strong in

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And I think it's good to review content from the beginning of the year too

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Since it's easy to forget them since it's been a while

wheat condor
#

<@&286206848099549185>

jagged raptor
alpine sable
#

yes please help i have been trying to submit this form for the last 30 minutes

warped phoenix
#

💀

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i forgot like...

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a lot....

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so videos it is then? 😅

topaz scaffold
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Yea ig

warped phoenix
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,w 1+2

warped phoenix
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oh wow that actually worked

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yay i can use wolfram

topaz scaffold
remote heron
loud mountain
#

,w 1+1+1

ocean sealBOT
loud mountain
#

Lol

topaz scaffold
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Which is 1*3

alpine sable
#

oh okay how did you get that result though

loud mountain
#

,w 1×3

ocean sealBOT
loud mountain
#

Sigh

warped phoenix
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doesnt this count as trolling???? lmfao

topaz scaffold
loud mountain
#

No

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Please

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That's enough

topaz scaffold
#

So 1+1+1 is succ(succ(1))

loud mountain
#

I don't want to lose my helper

warped phoenix
#

i meant

loud mountain
#

You can do it

warped phoenix
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the person asking

alpine sable
#

?

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isnt this a math server

topaz scaffold
#

Yep

warped phoenix
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yeah in which you're asking a blatantly obvious question

topaz scaffold
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Serious question: Do you know how to do addition?

warped phoenix
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thus trolling

alpine sable
#

@jagged raptor

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i think they helped but they didnt ping you

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so there you go

topaz scaffold
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Is it possible to be able to use Discord without knowing addition?

warped phoenix
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hmmmmmmmmmmmmmmmmm

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yes?

topaz scaffold
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Hmmmm

warped phoenix
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you dont need to know addition to make an email and register to the site ig

topaz scaffold
#

Seems plausible yeah

alpine sable
#

if it's so "blatantly obvious" then why did you need to ask a bot to do it lol

jagged raptor
warped phoenix
#

because i didnt know wolfram worked for me lol

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so i tested it out

topaz scaffold
#

It works for everyone

alpine sable
warped phoenix
alpine sable
#

true, true

topaz scaffold
#

Fancy technology

warped phoenix
#

i wonder

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if you know your life's career

alpine sable
#

oh wait this makes sense
if i use the formula δ(ψ) = ωψ + π, ω, π ∈ R

warped phoenix
#

why get taught things you dont need for that career

topaz scaffold
#

Oh thank goodness

warped phoenix
#

im pretty sure i dont need AP Calc BC for orthopedics......................................

topaz scaffold
#

Is that like a bone doctor?

warped phoenix
#

yeah

topaz scaffold
#

Ah

warped phoenix
#

idk man im with elon on this one

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his school teaches you specifically towards your interests

topaz scaffold
#

Is calc required at your school?

alpine sable
#

yeah after applying tai's method this problem is super trivial, thanks for the help kekw

topaz scaffold
warped phoenix
#

good colleges*

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lol

topaz scaffold
#

Ah

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I'm stuck in AB Calc because of Covid

warped phoenix
#

calc sounds fun

jagged raptor
warped phoenix
#

not really

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but yk

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sounds terrible tbh

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but yeah

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LOL

topaz scaffold
#

Oof spelling

topaz scaffold
jagged raptor
warped phoenix
#

man if i could take all science classes that didnt require math i would 😦

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no chem, no physics

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just bio ❤️ ❤️ ❤️

topaz scaffold
#

Doesn't bio use math later on?

warped phoenix
#

hope not

topaz scaffold
#

I'm not sure but I think I've heard something about it

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Ripppp

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"We have developed a set of application examples for Calculus, which are more biology oriented. These include: growth/decay problems in any organism population, gene regulation and dynamical changes in biological events such as monitoring the change of patients' temperature along with the medications."

astral dagger
topaz scaffold
#

Cool

warped phoenix
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😦

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me no likey math

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me hatey math

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very much

topaz scaffold
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Me likey math tho

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🥲

warped phoenix
#

like..i have no problem with complex rhetorical analysis of english literature or describing how in the period 1450-1750 certain states in Asia and Africa adopted policies to limit European power and influence

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but when it comes to "what is 1 + 1?"

abstract portal
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lol

warped phoenix
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i hate it

quick spoke
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heyaa, a friend sent me this question with solutions and I’m trying to do it myself but I’m a little stuck

placid zinc
#

Just looking for the area?

quick spoke
#

oh no just in general like how can I find the coordinates of D?

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or how did they find the rule of AD

placid zinc
#

What's the line that connects B and C?

quick spoke
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shouldn’t it have the same gradient as A and D but with a higher y intercept?

placid zinc
#

Yes

quick spoke
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but how do I continue from there?

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I don’t know the coordinates of B or D and I’m clueless as to finding it 😅

placid zinc
#

Or, sorry, you already have the equation AD. Okay, what's the intersection of AD and CD

quick spoke
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wouldnt you do simultaneous equations

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but the equation for AD is kinda

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not known

hushed blade
#

ad is just -0.5x

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oh it says that

quick spoke
#

I know, the answers are there

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I just want to figure it out how they got that :)

hushed blade
#

its perpendicular so the gradieent is the negative reciprocal

quick spoke
#

so the reciprocal of the gradient of y=2x-6 is 1/2

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and then negative

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so -0.5

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ohhhggg

hushed blade
#

yup

quick spoke
#

tysm it’s clear now

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:D

manic glade
#

why is it {i} and not just i?

sly mantle
#

the notation is for preimages of subsets of the codomain

manic glade
#

i guess the notation only works for sets?

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beat me to it

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is "uphold" or "fulfilled" used when you want to say something [] a definition/requirement?

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for example in this

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is there some other term?

sly mantle
#

satisfy

manic glade
#

👍

misty holly
#

what does this mean for rational numbers? b≠0

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𝑎 ≠ 0 for reciprocals

misty holly
#

can anyone confirm this pls?

wary stream
#

If a rational number is $$\frac{a}{b}$$ then the denominator can't be 0, hence $$b \neq 0$$ because you can't divide by 0

ocean sealBOT
#

dldh06

gaunt magnet
misty holly
#

oh okay, thanks for confirming!:)

wary stream
#

Same logic with $$a \neq 0$$ for reciprocals because it'll be $$\frac{b}{a}$$

ocean sealBOT
#

dldh06

misty holly
#

you know what? my module is irritating me, it keeps putting in things without even saying what it means

alpine sable
#

is the projection of v onto u equal to the projection of u onto v?

stark trail
hearty aurora
#

No they are different, if you are expecting a vector after your “projection.” They point in different directions unless u and v point in the same direction, in which case they would only be the same if they had the same magnitude

manic glade
#

if i have sets A_i which are sets of functions

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and i want to say there are functions which belong to more than one of these sets

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what is the phrasing

#

different A's? different A_i's?

#

belong to? are in?

stone pond
#

I'd write something like 'f belongs to several of the A_i'

manic glade
#

isnt it super weird to say several A_i's tho?

#

A_i kind of implies its a specific A which is indexed by some i

warped phoenix
#

is this channel free

manic glade
#

ish, i wouldnt mind more input on the phrasing but its not being actively discussed atm so ask away

sly mantle
#

@warped phoenix occupied

warped phoenix
sly mantle
#

the discussion isn't completely closed so it's best to treat the channel as occupied

warped phoenix
#

oh ok

sly mantle
manic glade
#

i dont quite know what family is yet besides context based intuition

#

but what if i is only 1 to 4 and a function can be only in up to two A's

sly mantle
#

@wicked gazelle occupied

wicked gazelle
#

Qn. 1.(iii)

manic glade
#

this is what i am trying to rephrase

wicked gazelle
sly mantle
#

family is a common name for a collection of sets

manic glade
#

belong to the family {A_i}?

#

still leaves the second sentence there

#

i need the emphasize the two

sly mantle
#

ok if that's all you want to reword, then

manic glade
#

just dont know if i can refer to it as A_i or A is better

sly mantle
#

there exist distinct indices i,j where f is in A_i and f is in A_j

jovial forum
#

Does what I've done here make sense? Trying to solve for y

sly mantle
#

@jovial forum occupied

manic glade
#

hm

#

would i need to define and explain j or would it be self explanatory as is

#

also as a general phrasing thing, should i just always avoid saying different A_i's?

sly mantle
#

the sets are implicitly defined over an index set. i,j are elements of that index set

manic glade
#

sounds good

queen nova
#

I can't tell what the coeffcient of c is

#

I think I'm just stupid

#

<@&286206848099549185>

sly mantle
#

@queen nova pls wait 15min before pinging helpers

queen nova
#

Oh sorry

willow wadi
#

so kind

#

of u

#

sir

clear vessel
#

How do I solve |x-2| = |x+2| algebraically?

novel crag
clear vessel
#

wdym

novel crag
#

Coz that’s modulus function

clear vessel
#

I know how to solve it graphically but for algebraically im confused

novel crag
#

for x>_2 , x-2=x+2 , and for the other case , 2-x=x+2

clear vessel
#

wdym haha

novel crag
#

|x-a| , means it will open either x-a or a-x , that’s the property of modulus function

clear vessel
#

oh

novel crag
#

If x>_a , then x-a , or else a-x

#

Refer to the definition of modulus functions again

clear vessel
#

How do I write 02≤x≤12 in the form |x-a|≤b

#

I've forgotten lol

novel crag
#

Wait a sec

gray isle
#

wdym by 02

hearty aurora
clear vessel
#

yeah I just figured

#

after that

#

I just subtract right to find the difference

wheat condor
#

<@&286206848099549185>

hearty aurora
#

hm no

novel crag
#

I mean 7

clear vessel
#

x-5*

novel crag
#

x+5€[-7,7]

hearty aurora
#

wait 7 is the midpoint though...

#

so it should be

clear vessel
#

|x-5|≤7

hearty aurora
#

|x - 7| < 5

clear vessel
#

I think should be other way rnd -7+5 = -2

#

oh wait I sent wrong questio

#

-2≤x≤12 in the form |x-a|≤b

hearty aurora
#

gotcha in that case, then i think youre correct

clear vessel
#

thanks for the help

hearty aurora
#

no worries 🙂

warped phoenix
#

so

#

the vertex of a quadratic in vertex form

#

is just (h, k)

ocean sealBOT
#

TheMane3

warped phoenix
#

be (-2, 3)?

rigid smelt
#

because the vertex form of a quadratic equation is said to be y = a(x**-** h) + k

#

if you plugged in h=2, it would have been x-2 and not x+2

warped phoenix
#

ohhhh

#

the x-h is a part of the vertex form so the negative doesnt apply to the x itself for the vertex

#

if that makes any sense

#

lmfao

novel crag
#

What?

rigid smelt
#

it doesnt make sense but as long as you get it then

#

🤷‍♂️

warped phoenix
#

ok so

#

(x-h)

#

wait

#

nvm

#

i get it lol

clear vessel
#

How do I solve |x-3| < |x+3|

rigid smelt
#

try to "remove" the absolute value appropriately

gray isle
#

consider the 3 cases

clear vessel
rigid smelt
#

no, do what ramonov suggested

clear vessel
#

how

rigid smelt
#

|x-3| and |x+3| has x=-3 and x=3 as their breaking points accordingly

#

consider what happens when x<-3

#

-3<x<3

#

and x>3

clear vessel
#

still confused haha

rigid smelt
#

for example when x<-3, |x-3|=-(x-3) and |x+3|=-(x+3)

#

this is how you are supposed to remove the absolute value sign

willow wadi
#

@ionic jewel

alpine sable
#

hi everyone i just joined the server cause i just got into collage

willow wadi
#

@ionic jewel

ionic jewel
#

dont ping me

rigid smelt
#

the channel is currently occupied so try not to interrupt the conversation, and please dont try to ping random users

ionic jewel
#

oh nvm

rigid smelt
#

unless you are friends or closely related

ionic jewel
#

nice image

#

i appreciate it

#

can go with

#

okay im done spamming this chat but thanks

wheat condor
willow wadi
neat haven
#

How do I factor this?

wind bane
#

can u factor 2y^2 + 3y - 2?

alpine sable
#

<@&286206848099549185>

neat haven
#

Yeah

#

Its the e to the xth which is messing me up

wind bane
neat haven
#

Do I just treat it as a whole?

compact hornet
#

let $y=e^x$

wind bane
#

let y = e^x

ocean sealBOT
#

juliandroske

wind bane
#

yea

wind bane
candid thistle
#

They probably wanted to annoy them or smth

alpine sable
#

@wind bane yes

#

@candid thistle no mate i need help lol

candid thistle
#

Ahh okay

alpine sable
#

i just joined so idk who to ask where to ask

wheat condor
#

any1 know this ?

wind bane
#

what have u tired so far?

warped phoenix
#

hey all

#

im trying to factor $6x^2 + x -15$

ocean sealBOT
#

TheMane3

warped phoenix
#

using the slide and divide method

#

can anyone help me understand why im not getting a reasonable answer?

#

i multiply -15 with 6

#

to get $x^2 + x -90$

ocean sealBOT
#

TheMane3

thorn kindle
#

Thats not how factoring works lmao

warped phoenix
thorn kindle
#

Find factors of ac that add to equal b

compact hornet
warped phoenix
#

i tried replicating this

#

with $6x^2 + x -15$

ocean sealBOT
#

TheMane3

warped phoenix
#

and im curious as to why it wont work

wheat condor
#

ay @compact hornet mad appreciate it g tjanks alot

#

can u clairify that some things said the i cant read it

thorn kindle
#

Ok so the problem is you need factors of -90 that add to equal 1

#

So -9 and 10

#

(x-9)(x+10)

warped phoenix
#

right

warped phoenix
# thorn kindle (x-9)(x+10)

but trying to divide both -9 and 10 by 6 gives you a decimal, so according to the rules you have to drag it to the x, so (6x - 9)(6x + 10)

#

and for obvious reasons

#

thats wrong

#

but i was told this method should be fine for all factoring

#

but apparently not, so i want to know under what condition can i not use this method

#

is it when the middle x has a coefficient of 1?

thorn kindle
#

9/6 = 3/2
10/6 = 5/3

#

Then you will get (2x-9)(3x+10)

#

Which should work

warped phoenix
#

omg

#

ughhhhhhhhhhhhhhhhhh im so fucking dumb

thorn kindle
#

,w expand (2x-9)(3x+10)

warped phoenix
#

yeah idk why i kept dragging the a term to the x's instead of the number you're dividing by

#

lmao even though it says right there what to do

#

🤦‍♂️

thorn kindle
#

No that doesnt work either

warped phoenix
#

yeah

#

ur right

#

hmmm

#

welp

#

then it goes back to "under what condition can I not use this method"

ocean sealBOT
#

TheMane3

warped phoenix
#

anyone else know?

thorn kindle
#

Ok let me show you how this method actually works

#

I read up on it its actually pretty nifty

#

Ok let us start with the polynomial

#

$6x^2 + x - 15$

ocean sealBOT
thorn kindle
#

Now let us multiply through by the leading coefficient

#

$6(6x^2 + x -15) = 36x^2 + 6x - 90$

ocean sealBOT
wheat condor
#

anyone here know calc

#

?

thorn kindle
#

Then let us rewrite the expression

jaunty crane
#

please help me on 3 questions

warped phoenix
#

isnt it just the 6 times the -15

#

or were the instructions wrong

thorn kindle
#

$(6x)^2 + (6x) - 90$

ocean sealBOT
thorn kindle
#

Now let $p = 6x$

ocean sealBOT
thorn kindle
#

so now we have $p^2 + p - 90$

ocean sealBOT
thorn kindle
#

We factor and get $(p-9)(p+10)$

ocean sealBOT
thorn kindle
#

then we substitute back in for p = 6x

#

$(6x-9)(6x+10)$

ocean sealBOT
thorn kindle
#

but now we have to divide by the leading coefficient again because we multiplied through by the leading coefficient

#

so it is really

#

$\frac{1}{6}(6x-9)(6x+10)$

ocean sealBOT
thorn kindle
#

,w expand 1/6(6x-9)(6x+10)

thorn kindle
#

@warped phoenix

#

understood?

jaunty crane
warped phoenix
jaunty crane
#

help pls

warped phoenix
#

delete ur msgs and post in a free channel

thorn kindle
#

this process gives you the correct roots. but in order to get the original polynomial back you must divide by the leading coefficient again

#

so in this case you have to multiply by 6, then divide by 6

warped phoenix
#

divide by 6 a second time?

#

and at the beginning should i multiply the whole polynomial by the "a"?

thorn kindle
#

you start with $ax^2 + bx + c$ $\newline$
then you multiply through by a:$\newline$ $a^2x^2 + abx + ac = (ax)^2 + b(ax) + ac$$\newline$
then you introduce a variable $p = ax$, and substitute: $p^2 + bp + ac$$\newline$
then you factor normally and get the following expression in terms of p: $(p-r)(p-s)$$\newline$
and then you substitute back in for $p=ax$, which gives you: $(ax-r)(ax-s)$$\newline$
but this is the polynomial that has been multiplied through by p. in order to get the original polynomial you need to undo the multiplication by dividing, yielding: $\frac{1}{a}(ax-r)(ax-s)$

ocean sealBOT
thorn kindle
#

it still gives you the correct roots though even if you don't divide. it's just that the polynomial will not be the same

#

in our example we arrived at: $\frac{1}{6}(6x-9)(6x+10)$

ocean sealBOT
warped phoenix
# ocean seal **AMD**

so what you've just written out here is basically the fixed version of what i sent you

#

that should work for all factoring right?

thorn kindle
#

yes

warped phoenix
#

oh ok

#

awesome

#

also yeah i read through it a couple times

#

but

thorn kindle
#

do you understand why it works? it's actually really cool

warped phoenix
#

it seems that the final answer ends with 1/a(ax-r)(ax-s) every time

#

is that allowed as like an answer

#

just having the 1/a out there

#

if im factoring

thorn kindle
#

that's what i was about to tell you.

warped phoenix
#

ah

thorn kindle
#

if you really want it without the leading coefficient in front you do this:

#

1/a(ax-r)(ax-s) = (x-r/a)(ax-s) = (ax-r)(x-s/a)

#

it will not always be an integer though. what you were given assumes that either r or s is divisible by a. which is not always the case

thorn kindle
#

$\frac{1}{a}(ax-r)(ax-s) = (x-\frac{r}{a})(ax-s) = (ax-r)(x-\frac{s}{a})$

ocean sealBOT
warped phoenix
#

ohhh

#

so either the r/a or s/a works

#

and like you said r or s has to be divisible by a

thorn kindle
#

yeah otherwise this method doesn't work as described. r/a or s/a will not always be an integer

warped phoenix
#

awesome

#

ty!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

#

so if thats the case btw

#

i should just stick with the ac method?

#

or some other way of factoring

thorn kindle
#

your choice really. i was personally taught another way

warped phoenix
#

oh ok

thorn kindle
#

which imo i prefer. but i see the logic behind this one

warped phoenix
#

dang it i was hoping this method would work for everything because i despise all other forms of factoring but not in this life it seems 😠 😭

thorn kindle
#

it does work

#

as i described it to you

warped phoenix
#

but you said only if r or s is divisible by a

thorn kindle
#

no it still works for all quadratics.

warped phoenix
#

ohhhhhhhhhhhh

#

YAYY

thorn kindle
#

it's just that you will have rational numbers inside the parantheses instead of just integers

#

if you want i can show you the method i learned. it's actually a lot easier

warped phoenix
#

than yeah absolutely

thorn kindle
#

alright

#

let's use the same quadratic

#

$6x^2 + x - 15$

#

right?

warped phoenix
#

sure

thorn kindle
#

or wait no

ocean sealBOT
thorn kindle
#

this is it?

warped phoenix
thorn kindle
#

alright. now find the product ac

warped phoenix
#

a*c = -90

thorn kindle
#

alright. now find two factors of ac that add to equal b

alpine sable
#

hey guys

#

oh wait u guys in the middle of a conversation sry for interupting

warped phoenix
thorn kindle
#

now watch.

warped phoenix
jaunty crane
#

ok

thorn kindle
#

made a typo gimme a sec

#

$6x^2 + x - 15 = 6x^2 + 10x - 9x - 15 = 2x(3x+5) - 3(3x+5) = (2x-3)(3x+5)$

ocean sealBOT
jaunty crane
#

ok

thorn kindle
#

basically you factor by grouping. and it always works regardless of how you split the linear term

#

@warped phoenix

warped phoenix
#

ohhhhhhhhhhh

#

i see

#

i think ive seen this before yeah

#

so you just need to find a*c, the factors of ac that add up to the middle term, and then replace the middle term with + ax + cx, put it into 2 groups, factor out if factorable (actually nvm it has to be factorable for this to work which im assuming it would be factorable every time) and then put the repeating part into its own group and then what was factored out into its own group

#

is that right? the process i wrote out @thorn kindle

thorn kindle
#

yeah pretty much i think you get the idea

warped phoenix
#

oh ok

#

wow this is quicker

#

ty!!!!!!

thorn kindle
#

😎

mystic hemlock
#

Hello I am new here

#

who is owner of this server

alpine sable
#

damn @thorn kindle u are very smart and helpful !

warped phoenix
#

hey guys

#

does anyone know how i could turn a number into a simplified radical using my ti84?

candid thistle
#

wont it just be basic normally?

warped phoenix
tight locust
#

you can't do it on a ti84. it's not designed that way

#

unless you have a special app

candid thistle
warped phoenix
#

where could i find such an app 😈

tight locust
#

look for CAS calculators. (computer algebra system). these work in the same way wolfram alpha does where they are able to manipulate math symbolically instead of just using floating point numbers

mystic hemlock
#

derivative of log(sin(cos x))

alpine sable
tight locust
#

you can just google "(your model of calculator) simplifying radicals app"

#

something like that

#

is it the ce?

warped phoenix
#

it is yeah "Ti-84 Plus Ce"

warped phoenix
#

so yeah i want something to where if i wrote in "sqrt(-48), instead of giving me "6.928i" it gave me "4i*sqrt(3)"

quaint edge
#

Hi, I was just wondering in Gauss' elimination method in linear algebra, how can we do stuff like do (1-2)row1 + row2 and still have row1 be completely unchanged?

wheat condor
#

<@&286206848099549185>

vale wigeon
#

it's ,rotate with a comma fyi

#

,rotate

ocean sealBOT
trail mantle
#

How do u reduce an ODE to an ODE with constant coefficients?

shell iron
#

any clue what this table is?

#

<@&286206848099549185>

alpine sable
#

What’s the surface area formula for a triangular prism?

wind bane
gray isle
#

apply the definition of surface area

manic glade
#

why is k=n-1?

vale wigeon
#

nobody is claiming that

#

here the identity $\binom{m}{r} = \binom{m}{m-r}$ is used

ocean sealBOT
manic glade
#

and why is that true

tight locust
#

symmetry

vale wigeon
#

what's your definition of the binomial coefficient?

#

is it the factorial formula or is the combinatorial one

manic glade
#

whats that

vale wigeon
#

this thing were talking about

#

$\binom{n}{k}$

ocean sealBOT
tight locust
#

look at pascal's triangle

vale wigeon
#

are you defining it as $\frac{n!}{k!(n-k)!}$ or are you defining it as the number of subsets of $1:n$ of size $k$

ocean sealBOT
manic glade
vale wigeon
#

okay so youre defining it through factorials

#

great

#

$\binom{n}{n-k} = \frac{n!}{(n-k)!(n - (n-k))!} = \frac{n!}{(n-k)! k!} = \binom{n}{k}$

ocean sealBOT
manic glade
#

neato

#

thanks

#

wait actually, how do you solve that

willow wadi
#

hi

vale wigeon
#

solve what

willow wadi
#

now

#

emergency

manic glade
#

oh nvm lel

willow wadi
#

lock down

manic glade
#

just sleep deprived

willow wadi
#

?av

alpine sable
wide raven
#

Why are matrices multiplied the way they are?

#

I've heard they are used somehow in vectors

#

I need some elaboration

wind bane
#

matrix multiplication is defined in exactly the right way to correspond to the composition of linear maps

tough hatch
# wide raven Why are matrices multiplied the way they are?

Multiplying two matrices represents applying one transformation after another.
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gritty cave
#

how do i solve this

gray isle
#

apply factor theorem

gritty cave
#

@gray isle is it 7?

gray isle
#

yes

wide raven
alpine sable
rancid nexus
#

@alpine sable ?

alpine sable
#

Because the third loop is not inside the second loop their times arent multiplied, they are added

#

tô hảd

#

too hard

#

So indeed the time complexity is n^2

#

Actually not even, it is at most n^2

#

Looks like it’s actually min(A.length,B.length)

#

@rancid nexus

#

Although this is quite a weird algorithm

#

yes

slow haven
#

can I post a question here?

rancid nexus
#

@slow haven yes i am done

slow haven
#

thanks

#

got this sent to me

#

dont know where to start

jovial forum
#

Starting with dP/dt = 0.0005P(2000-P), find P(t)

#

how do I do this?

stark trail
#

then integrate both sides

jovial forum
#

So I wind up with P = Pt-0.0005P^2*t

#

or P(t) = Pt-0.0005P^2*t I guess?

#

Do I need to do anything else?

#

anyone?

icy gyro
jovial forum
#

Thanks

icy gyro
#

just

#

the t is not a part of the power

jovial forum
#

oh yeah

#

ty

icy gyro
#

np!

jovial forum
#

So there should actually be a constant there. So P(t) = Pt-0.0005P^2*t + c, if P(0) = 100 then c = 100 right?

icy gyro
#

yep

jovial forum
#

So let's say I wanted to find when P=500, do I just sub 500 in for each P, then solve for t?

icy gyro
#

yess