#precalculus

1 messages · Page 264 of 1

terse ravine
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It's wrong

uncut mulch
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which is bigger

viscid thistle
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your answers are correct, but in the wrong place

terse ravine
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Was a silly mistake.

celest void
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@lusty falcon use in conjunction with sin^2 a + cos^2 a = 1, see if you can write cos (2a) purely in terms of cos

echo pelican
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Can someone help me with this problem 22 here? Im helping a student with precalc and this is the only thing on their practice exam I cant figure out

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I know there is a sec(pi/2 - x) identity but this one is (pi - x)

viscid thistle
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Do you know cos(pi - x)

echo pelican
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Know only sec(a)

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Just what it says there

viscid thistle
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do you know it's identity I mean

echo pelican
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No i do not

viscid thistle
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do you know cos(pi/2 +x ) ?

echo pelican
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I know theres a pi/2 - x for each trig function

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But i do not know how to invoke those for this question

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I thought it must be a typo the precalc trig stuff usually comes directly from the identities but i was wondering if there is something simple i am overlookimg

cerulean quarry
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ok 1 sec

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u need 22 answered right/

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?

echo pelican
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Yes

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That is all the given information there

cerulean quarry
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f(a)=11/3 and f(theta)=sec(theta)

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u want f(pi - a )

echo pelican
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Yes basically

Sec(a) = 11/3

Find Sec(pi-a)

cerulean quarry
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first u need to solve for A

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yes

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do u know how to do that?

echo pelican
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Well i think this wants an exact value

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And no calculator

cerulean quarry
#

that might be hard

echo pelican
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My impression is that it was meant to be a trig identity problem

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But there was a typo

cerulean quarry
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i dont remember the identity but all u do is solve for A

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does is explicitly say that u need a exact answer?

echo pelican
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We can solve for A in terms of cosine inverse function, but based on the problems around it i assumed it was supposed to be a trig identity problem

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I guess it just says "value"

cerulean quarry
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well its cosine 3/11 that doesnt come out very pretty

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and ur subtracting it from pi so its still not going to be pretty

echo pelican
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There's an identity for pi/2 so my thought is that they meant to write that

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Pi/2 - x

cerulean quarry
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for secant or cosine?

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duh both ><

echo pelican
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For every trig function

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Lol yeah

cerulean quarry
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let me check some trig identities real quick

echo pelican
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Every basic* trig function

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Thank you

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I just wanted to make sure i was not overlooking something simple here

cerulean quarry
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yeah i dont think so

echo pelican
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Or what if you combined double angle identity with the (pi/2 - x) ?

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Factor 2 out and treat it as double angle

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Well wed have a/2 tho...

cerulean quarry
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the problem is the 11/3 isnt a nice point on the unit circke

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so no matter how u rotate it by those angles its still going to spit out an ugly number

echo pelican
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Ok thank you im gonna try to take a crack at it mixing and matching identities but i thought it must be a typo

cerulean quarry
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ok

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i wouldnt solve for an exact answer at all i'd just leave it as an expression imo

echo pelican
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Yeah i think there is no choice as written

cerulean quarry
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the question looks likes its testing to see if u know how to solve for a

echo pelican
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Maybe that is the case but this one was with like 4 trig identity problens in a row

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And it is one division by 2 away from being an identity

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Thank you very much for taking a look with me

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I was afraid i was missing something very obvious

cerulean quarry
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actually i didnt check what would happen if u put them in fraction form

echo pelican
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How do you mean?

cerulean quarry
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actually no nm

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nm that

echo pelican
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Ah oj

cerulean quarry
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i think its as i said it was

echo pelican
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Ok*

cerulean quarry
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i thought of it then in came out wrong

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it

echo pelican
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Yeah seems to be no other way to answer it

viscid thistle
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cos (pi-x) = -cosx is a derivable thing

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If you know what cos(pi/2 +x)

echo pelican
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Is that a trig identity?

Cos(pi-x) = -cos(x) ?

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That must be it then if it is!

viscid thistle
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It is

echo pelican
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Thank you so much! I checked like 10 trig identity tables and none of them had that

viscid thistle
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Can someone help me with this problem?

queen vapor
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@viscid thistle what's the problem?

viscid thistle
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I’m supposed to verify the trig function

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But I don’t understand the first step...

queen vapor
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First of all, Tanx = Sinx/Cosx

viscid thistle
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Yes

queen vapor
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So, they used for the denominator

viscid thistle
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Ok

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Idk if you can see, but I sent a pic of the problem I’m working on

queen vapor
#

Yeah

viscid thistle
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Ok

queen vapor
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Yeah, best way is 2Cosx is common

viscid thistle
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Ok

queen vapor
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So, 2Cosx (1 - 1/1-Tanx)

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Now simplify the portion inside Parenthesis

viscid thistle
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Ok, and distribute right?

queen vapor
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yep

viscid thistle
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So would it look like this?

queen vapor
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( 1 - 1/ 1-Tanx)

viscid thistle
queen vapor
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Lemme use paper

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wait

viscid thistle
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Ok, thank you so much.

queen vapor
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You had everything right

viscid thistle
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Ok

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Thank you!

queen vapor
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Welcome

split epoch
uncut mulch
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Question 4:
incorrect range,
incorrect x-intercept

queen vapor
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,rotate

obsidian monolithBOT
queen vapor
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See the end points on the X axis

uncut mulch
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Question 5:
incorrect domain,

queen vapor
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like (-2,4]

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Since, the function is bounded

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so we have fixed range also

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oops

silver matrix
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How can I approach this problems?

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I know VA: 3
HA: y = 2
x-intercept (y=0): 4

willow bear
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i'd start with y = 2 + 1/(x-3) and then do some scaling and shifting to get the y-int right

silver matrix
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ok thanks

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why have you put 2 +1

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instead of 3?

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shifting and scaling i guess what I learnt on transformation functions, like multiplying x or summing to get a vertical or horizontal shift, etc

willow bear
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i didn't say $y = \frac{2+1}{x-3}$ god forbid

obsidian monolithBOT
silver matrix
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yeah, i mean u said start with that

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not that it was the final solution i know

willow bear
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i said $y = 2 + \frac{1}{x-3}$ and honestly i'm really upset you read the 2 as being in the num

obsidian monolithBOT
silver matrix
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i'm sorry :(

willow bear
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you can find a function of the form $y = 2 + \frac{k}{x-3}$ where $k$ is a constant

obsidian monolithBOT
silver matrix
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any resources you could share with me?

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I... i don't know how to do it

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nor why start from that

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I only understand the x - 3 for the VA

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but not why doing the rest of it

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ok

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what is the meaning of scaling?

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2 + 2/x-3 satisifies the VA and the x-intercept

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ok, now I see my problem

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HA is not y = 2

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well yes

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but not directly doing 2 = 2 + 1/x-3

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ok, problem is i need another x

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how am I going to get both y = 0 and y = 2

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that's the problem i hav

willow bear
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PARENTHESES

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\verb|1/x-3| reads as $\frac{1}{x} - 3$, not as $\frac{1}{x-3}$. spacing is not a substitute for parentheses.

obsidian monolithBOT
willow bear
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nor why start from that
it's a bit arbitrary but the form i gave you is relatively simple

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just require that the curve pass through (4,0) and you'll get an equation in k which can then be solved

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@silver matrix honest to god you're just kinda really overthinking this rn

echo pelican
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The horizontal asymptote occurs when you have the same degree in numerator and denominator

silver matrix
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@silver matrix honest to god you're just kinda really overthinking this rn
nah, I'm not. I'm just dumb. I don't understand how someone can be so cool, that by giving some premises can build a function. I don't see a way that can find any function you want; that would be even cooler

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my god

willow bear
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i'm not looking for ALL rational functions which satisfy this

silver matrix
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yes I know

willow bear
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i'm just giving one of many possible methods

silver matrix
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👍

rare zephyr
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does a. means h(t) = 0?

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does b. means do I have to differentiate it twice or once?

viscid thistle
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does a. means h(t) = 0?
@rare zephyr looks like it

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Though it could've been stated it more clearly

rare zephyr
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alright

neat birch
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does b. means do I have to differentiate it twice or once?
you need to find the maximum and minimum heights, meaning that the derivative of that formula will intersect with the x axis

chrome thorn
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Is there an asymptote to a square root function?

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If its a rational function inside the square root

blissful ridge
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I didn't write out all the steps

But we can say that it holds from there, right?

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@willow bear
Sorry for the ping, that channel was occupied

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Ignore the quality of pages

velvet blade
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@blissful ridge bro in the second page on RHS, isn't that supposed to be (3n+3)/2?

blissful ridge
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Where??

blissful ridge
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Actually in the first page I wrote divided by 3 by mistake

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It should be 2

velvet blade
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Oh okayy

hearty vector
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ik how to get the VA, HA, Hole, xint, y int

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i just have trouble graphing it by hand

viscid thistle
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same steps as every function

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If you have all that info, i don't know where do you have troubles

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Start by imagining an idea of how it'll look

hearty vector
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i also dont understand how the line in the middle happens

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when there is a H.A. at y= -1

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my math is questionable pepega

viscid thistle
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What?

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How the line appears???

hearty vector
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i mean like

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the third line in the middle

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goes through y = -1

viscid thistle
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Yeah so what

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A horizontal asymptote can be perfectly crossed

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do you agree that an asymptote is a line?

hearty vector
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uhh sure?

viscid thistle
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the HA is just there to indicate us end behavior

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horizontal asymptote is a behaviour of the function for very big x

hearty vector
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i havent learned what lim is yet

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horizontal asymptote is a behaviour of the function for very big x
@viscid thistle as x goes to the extreme value of it right?

viscid thistle
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yes

hearty vector
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ok

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so i guess now my main question is, how do would i graph this by hand? do i literally just graph the intercepts, and plug in test points?

viscid thistle
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Start by imagining an idea of how it'll look
then, organise and represent your data obtained (HA, VA, x-intercept, y-intercept) and make sure you mark everything first

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and then draw the line

hearty vector
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what are some key things that i should consider by imagining how it'll look?

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the degree?

viscid thistle
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do you know about derivatives?

hearty vector
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nope

viscid thistle
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basically your data obtained, HA, VA, x-intercept, y-intercept, domain, maybe range

hearty vector
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ik the difference quotient

do you know about derivatives?
@viscid thistle

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Lul

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basically your data obtained, HA, VA, x-intercept, y-intercept, domain, maybe range
@viscid thistle ok, i'll give it a go

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thank you

viscid thistle
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domain is very important

hearty vector
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mhm

viscid thistle
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also when f(x)>0 is a very useful one

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yeah but ig they haven't learned derivatives so i didn't include it

hearty vector
#

thank you for the help!

mighty crater
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yo I need help with a question

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For the following function, sketch the reciprocal. State all key points and properties. (App 8)

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this is Rational Functions unit

full pagoda
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find values for f(x) and flip 'em @mighty crater

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for example, f(3) = 4 so the reciprocal is 1/f(3) which is 1/4

mighty crater
mighty crater
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I need help with this question

jagged orbit
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how can i construct a function such that lim f(x) x-> -4+ is 0 and lim f(f(x)) x -> 4+ DNE, is not +/- infinity
and also of domain r?

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could anyone help :/

jagged orbit
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<@&286206848099549185>

mighty crater
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<@&286206848099549185>

junior sable
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can someone please explain to me how 16^(3/4) = (16^(1/4))^3? I get that it's what I'm supposed to do, but I don't understand how it works.

mighty crater
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Use photomath

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@viscid thistle what grade u in

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Yooooo

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I need help with this

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@viscid thistle bro

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yea plz

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these are marks lol

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yea

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those are just marks

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like for the question

wraith idol
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$\frac{(x-1)(x-2)}{(x-1)(x-2)}$

obsidian monolithBOT
mighty crater
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Man, yall are confusing the hell out of me. I just need this for my assignment due tmrw

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So u don't know this... @viscid thistle

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For the following function, sketch the reciprocal. State all key points and properties

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how about this

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@wraith idol how about this question

mighty crater
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@wraith idol is the slant asymptote the same as an oblique asymptote?

wraith idol
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same thing

mighty crater
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ok thanks

mighty crater
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when is it asking for Interval(s) when the graph is above the x-axis and below the x-axis for f(x)= 1/x^2 What does that mean, how do i do it @wraith idol @viscid thistle

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bottom 2

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@viscid thistle

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@wraith idol

bitter sandal
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hello i need some clarification regarding the sequence * 1 + 1/4 + 1/9 + 1/16 + ... + 1/n^2 *

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does the n mean that it continues forever?

harsh socket
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hello i need some clarification regarding the sequence * 1 + 1/4 + 1/9 + 1/16 + ... + 1/n^2 *
@bitter sandal la n significa que llega hasta un numero especifico

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the n means that it reaches a specific number

bitter sandal
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so the number terms of this sequence would also be "n" ?

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hmm i starting to kinda get it now, thank you

harsh socket
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so the number terms of this sequence would also be "n" ?
@bitter sandal Si hablas de como queda la sumatoria ya cuando converge, pues si deberia quedar en terminos de n

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If you talk about how the sum is already when it converges, then if it should be in terms of n

bitter sandal
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ahh i see i see, that makes sense now. thank you

harsh socket
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🙂

mighty crater
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Anyone can tell me if these are right or not, and what is the last one?

steel venture
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your third one is wrong, your fourth justification could use some work

solid juniper
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Guys help please

steel venture
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@mighty crater

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@solid juniper send the question

mighty crater
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Can u tell me what is the 3rd on plz

steel venture
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no

solid juniper
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im dumb btw

mighty crater
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sry bro, there is so much goin on and im stressin

solid juniper
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So i wont understand anything right away

steel venture
#

no worries, the answer to the third one is much simpler than you think

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your justification is perfect, build a simple funciton around that justification

mighty crater
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ok

steel venture
solid juniper
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Ok

bitter sandal
#

can this be expressed in sigma notation? >> " -1/2, 1 -3/2, 2 -5/2, 3

the only solution i have gives me the fractions only

steel venture
#

pleura can you post the question

bitter sandal
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the instruction says: Express each sum using the summation notation

steel venture
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start by doing a simpler case, multiply all the terms by 2

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see what you get

bitter sandal
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uhhh negative 1

steel venture
#

?

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wait do you understand what the question is asking you to do

bitter sandal
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wait if you mean the entire thing.. uh 9

steel venture
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dont actually add them, just write out the sum

uncut mulch
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note that you tried to consider :"1 - 3/2" and "2-5/2" as single summands

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instead consider there to be 6 summands where the signs alternate

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in which case you could include something like (-1)^n

mighty crater
willow bear
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@mighty crater still need help with this?

solid juniper
chrome thorn
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How would I find the vertical and horizontal asymptotes of this function? The square root is confusing me

placid delta
#

How to find focus in this equation?

y^2+4x=0

viscid thistle
#

the focus

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id change it so its based on x

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y^2 + 4x = 0
x^2 + 4y = 0 (lol swap them, ill swap them back later)
x^2 = -4y
(x^2)/-4 = y

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then complete the square, and find the focus

dusk onyx
#

$f(x) = x^2+lx +(\frac{l^2}{4} - \frac{9m^2}{4})$

obsidian monolithBOT
dusk onyx
#

range is the set of all real values?

sour plinth
#

that's domain

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find the minimum value

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of f(x)

dusk onyx
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yikes

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i see

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thats alot of work

sour plinth
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do you know how to find the minimum value of a parabola

dusk onyx
#

algebashing

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i do

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its just annoying to do the algebra on that

sour plinth
#

i'd differentiate it

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wait nvm precalc

dusk onyx
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youre right i could

sour plinth
#

you can use -b/2a

dusk onyx
#

much easier that way

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im not on precalc level

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american education system is weird to me

sour plinth
#

the x value of the min/max of a parabola is always the average of the two roots

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so it would be -b/2a (for a parabola ax^2+bx+c)

dusk onyx
#

2x + l = 0

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so x = -l/2

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i put that in and find the y value

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and then y >= answer

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is the range right

mighty crater
#

@willow bear Yea i do

willow bear
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what a delay wow

mighty crater
#

my bad bro

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I had a lot of stuff that I had to do man

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My bad

willow bear
#

please don't bro me

grim canyon
#

^^ I respect ya Ann I am trans too 🙂 sorry that some people don't understand it.. but I do 🙂

#

@willow bear Sorry about ColdKurama bae

mighty crater
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ok I never knew tf, why are yall getting aggressive on me'

willow bear
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i wasn't aggressive in the slightest

mighty crater
#

Im simply asking for help

grim canyon
#

no were not aggresive

mighty crater
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Ok my bad

willow bear
#

anyway, i was busy when you replied

grim canyon
#

were just saying we are like this

willow bear
#

can you repost the problem

mighty crater
#

ok

willow bear
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it was about sketching the graph of 1/f(x) when that of f itself is given i think?

mighty crater
willow bear
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yeah ok so what have you done so far

mighty crater
#

No given equation

willow bear
#

you don't need the equation

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you just need to know how to visualize going from (x, y) to (x, 1/y)

mighty crater
#

i have a very rough sketch

willow bear
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oof no

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way off

mighty crater
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Yea i figured

willow bear
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ok so first off draw the lines y = ±1

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the points where your graph meets either of those lines? those are the ones that stay in place

mighty crater
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The problem is with the curve right?

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The lines are ok??

willow bear
#

everything is bad in your sketch

mighty crater
#

ok 😆

willow bear
#

zeros, as i said above, turn into asymptotes. there are no asymptotes in the original graph but if there were any they would become zeros

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there are several key points on the graph which can be transformed explicitly

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(1/2, -9/4)
(3, 4)
(4, 2)
(5, 3)

mighty crater
#

i may be wrong but when we transform these points, do we add a negative in front of the coordinates in order to make the reciprocal?

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@willow bear ?

willow bear
#

why negative

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you're not multiplying by -1

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you're going from y to 1/y

mighty crater
#

Ok i see now

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Thank u

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Ok i might have one more question later, if that doesnt bother u

grim canyon
#

I mean Ann isn't the only one that could help in this channel so dw

mighty crater
#

ok yall are saving my ass, I appreciate yall

grim canyon
#

xD

mighty crater
#

I think the 2nd one is wrong

random cloud
#

I just have to isolate y in terms of x right?

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And then do the same for x in terms of y again?

grim canyon
#

,rccw

obsidian monolithBOT
random cloud
#

Yes?

lime bolt
#

lol what else would u do

random cloud
#

How would you even solve this with compelteing the square

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Cuz I've seen some weird sifusruons involving fractions where you can find an exact amount

lime bolt
#

note that 2(y^2+xy)=2(y+x/2)^2 -x^2/2

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so u can just rearrange, square root and minus x

random cloud
#

Where did the 6 go

lime bolt
#

what?

viscid thistle
#

@sweet cliff PLEASE

lime bolt
#

16 consectuive messages spamming this one guy in different channels thonk

grim canyon
#

^^ yep..

mighty crater
cedar pawn
#

Whats a reciprocal

quaint mason
#

?

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in what

sick seal
#

i think of it as an opposite. think of the number 2 written out as 2/1. 1/2 is the reciprocal of 2 because multiplied together it = 1

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@cedar pawn

quaint mason
#

just swap the numbers.

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are u sure u asked the question in the right topic

sick seal
#

hit it with the good ol uno reverse to make it = 1

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i gotta question i just need a second to word it

quaint mason
#

i couldnt tell if he was kidding xD

sick seal
#

nvm i figured it out. rubber duck for the win.

quaint mason
#

lmao

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aight

viscid thistle
#

how do I do question b?

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i've been stuck on it for a while now

blissful ridge
#

What have you tried?

uncut mulch
#

the same way you did a)
just more algebra

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^

viscid thistle
#

i think I got it

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basically that (fog) (x) = x

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right?

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and then I try to simplify in order to try and get x

blissful ridge
#

Yeah

zinc chasm
#

Heya im in 8th grade

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and this is my hw lol

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im pretty bad at graphs so i need some explanations

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any help

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<@&286206848099549185> ?

idle moat
#

how do you solve this

full pagoda
#

what do you think your first step will be?

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@idle moat

idle moat
#

divide by 3

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after that, im a bit lost

full pagoda
#

Do you know what the opposite of euler's number is?

idle moat
#

no

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are you asking for the value of e?

full pagoda
#

the natural log is the opposite of e

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to get a variable out of the exponent, you take the natural log of both sides.

idle moat
#

so lne^x = ln (10/3)

full pagoda
#

correct

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and since ln is the opposite of e, they "cancel" out

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well they equal 1, at least

idle moat
#

i got it, thank you

full pagoda
#

no problem :)

idle moat
#

what about for

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i got down to the step

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log (6x - 24) = 2 log x

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actually

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log (6x - 24) = log x^2

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nvm lol, i got it now

full pagoda
#

one of those is wrong

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you wouldn't get log(6x-24)

idle moat
#

-8*

full pagoda
#

there you go

burnt owl
#

help

#

idk how to do d, f, c, and c

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help for any of them would be much appreciated

full pagoda
#

@burnt owl d is the same as f(x) + h(x)

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so x^2-3x-28 + sqrt(5-7x)

#

f is just plugging g(x) into itself for x

#

so whenever you see x in g(x), plug in the entire g(x) equation

#

c is the same thing except whenever you see an x in g(x), plug in h(x)

#

and then you put c twice and i'm not sure you meant to

burnt owl
#

oh

viscid thistle
#

@umbral haven remove this from here

#

And dont double post in future

umbral haven
#

yes sir

#

where does that question belong

#

calc or precalc

viscid thistle
#

Calc

#

Idk much about this precal and calc division

hallow bison
#

Can anyone help me solve this?

odd cloud
#

Apply linear velocity = angular velocity * radius, here in your problem liner velocity and radius are given.

flint pulsar
#

The size of a population of rabbits is determined by the rule P = $6400*30^{0.2t}-400$ where P is the size of the population t years after January 2006. Sketch the graph of P against t.

obsidian monolithBOT
flint pulsar
#

i was just wondering what does the e represent for the x-int?

willow bear
#

e is e

#

yknow, the base of the natural logarithm

delicate rivet
#

wait but what is a natural base of a logarithm? like what does it represent?

full pagoda
#

euler's number comes up everywhere. it's mostly related to exponential growth or rate of change

flint pulsar
#

okay, so how would it be applied in these types of questions? like when i solve for the x-int, how would i know to use e?

#

i also solved for the x-int on my calculator and it came up with a slightly different answer to the x-int provided

full pagoda
#

e is mentioned or can be derived in just about every growth formula there is

#

at least of the ones i can think of

#

so you'd know to use it based on a given formula

#

i know population growth formula has e in it

delicate rivet
#

ohhh, so you'd choose whether or not to use e depending on the situation in the problem?

full pagoda
#

pretty much

#

but when talking about population growth, it's in the formula

delicate rivet
#

wait what's your population growth formula?

full pagoda
#

The one that comes to mind for me is the Pert formula

#

P_0 * e^rt

#

where p_0 is initial population, r is rate, and t is time

delicate rivet
#

ohhh, so instead of a numerical value we use it, (for population growth)

full pagoda
#

when applying that formula, yes

flint pulsar
#

ohh that makes more sense thank you sm for your help!

delicate rivet
#

last question to double check; you'd basically use e for situations where we need a 'smoother' growth?

full pagoda
#

honestly i wish i knew more about it. i'm not sure about 'smoother'. most of what i'm basing this on is the fact that it is an essential constant when talking about growth/rate of change. if you're studying those topics, you will be seeing euler's number a lot

willow bear
#

e is just a number lol

#

the function e^x has some properties which set it apart from other exponential functions but those don't really come up until calculus

full pagoda
#

comes up in alg 2

delicate rivet
#

ooo okie, tysm for you help!

full pagoda
#

👍

bitter sandal
#

is this true? apparently my book doesnt say something about it, and i've searching in google but idk how do i word it out on the search bar

blissful ridge
#

Yes that is true

bitter sandal
#

thank you

cedar parcel
#

can some help me?

#

The problem I have is due tommorow

viscid thistle
#

@cedar parcel i can't help if you don't post the problem

fossil crownBOT
#
Rule 1

The help channels are solely for help with math, so feel free to post your question. Asking whether you can ask a question or if anyone knows about some specific topic is unnecessary, so please try to avoid questions of that nature.

viscid thistle
#

Yeah no don't multipost just realised

fossil crownBOT
#
Rule 3

Stick to one channel and don't post the same question in multiple channels. Please don't ask for help in other channels if no one is responding in the one you have posted your question in.

cedar parcel
#

can someone jsut help me?

#

*just

#

And i posted in multiple channels because one one is helping me

#

*I

viscid thistle
#

What kind of argument is that

cedar parcel
#

its not

#

its a fact

viscid thistle
#

So you are telling me you break the rules of the server just because you can't be patient?

cedar parcel
#

its due in an hour

viscid thistle
#

Well that's definitely not our fault.

mighty crater
#

My man is desperate

#

just help the man yo

viscid thistle
#

?

onyx saffron
#

我在试做数学作业,可是一问题得难。问题是“A Ferris wheel 50 ft in diameter makes on revolution every 40 seconds. If the center of the wheel is 30 feet above the ground, how long after reaching the low point is a rider 50 ft above the ground“。正确的答案是”55.903秒钟“,为什么?

viscid thistle
#

@onyx saffron still stuck?

onyx saffron
#

i got an answer but it isn’t 55.903, it’s 15.903, i don’t understand why 40 was added

vapid blaze
viscid thistle
#

At points of inflexion

blissful ridge
#

Rate of change is zero at that very instant but can we say it's constant??

onyx saffron
#

since it’s an odd power greater than one, the derivative is an even power and therefore it is never constant

#

i think

vapid blaze
#

It has an Odd power, so I was thinking the same

viscid thistle
#

Rate of change is zero at that very instant but can we say it's constant??
Hmmmm

onyx saffron
#

the derivative never remains constant, so there are no points where it has a constant rate of change

viscid thistle
#

Hmmm right

#

Mb

#

i got an answer but it isn’t 55.903, it’s 15.903, i don’t understand why 40 was added
@onyx saffron can i see what you did

vapid blaze
#

Thanks guys

viscid thistle
#

If you are still looking for help

onyx saffron
viscid thistle
#

That is literally ilegible

onyx saffron
#

ohh the watermark

#

give me a second

#

so i set up a triangle, used sign to find the angle, added 90 to that, divided by 360, multiplied by 40, and that gave me my answer

viscid thistle
#

Okay hold up

#

@onyx saffron okay

#

You there?

#

yo?

onyx saffron
#

sorry i was running

#

what did i do wrong ?

viscid thistle
#

everything until "divided 360" is correct

#

excluding diving by 360

#

so you have your angle arcsin(4/5)*pi/2

#

do you know the relevant formulas for time of revolution or angular velocity?

#

@onyx saffron

onyx saffron
#

i think so

viscid thistle
#

can you be more active?

#

if possible

#

if not it's okay but let me know

onyx saffron
#

i'm here

viscid thistle
#

okay

onyx saffron
#

i'm trying to get the angle in degrees, not radians

viscid thistle
#

is this familiar to you $\omega=\frac{2\pi}{T}$

obsidian monolithBOT
onyx saffron
#

nope

#

wait maybe

#

does that have to do with the period of a function?

viscid thistle
#

yes

onyx saffron
#

then yes, i have

viscid thistle
#

T is the time spent to complete one revolution

#

which you have

onyx saffron
#

ohh, okay

viscid thistle
#

so when we get the angular velocity we can finally solve for the time with $\theta=\omega t$

obsidian monolithBOT
onyx saffron
#

so i use that instead of /360

viscid thistle
#

with theta being arcsin(3/4)+pi/2

#

yeah working with angles works too obviously

#

but you need to be consistent

#

be careful with units

onyx saffron
#

that makes sense

#

thanks

graceful bear
#

how to solve circles?

viscid thistle
#

?

blissful ridge
#

We humans and even you hobo cannot understand such high level of communication

viscid thistle
#

This reaction plus HoboSas's pfp made me laugh so bad

#

?
I'm talking about this

#

Plus their dp

#

how to solve life problems?

#

Wait are you serious

#

no

#

how to solve circles?
@graceful bear

#

be more specific

#

I guess we will never find out

graceful bear
#

Conic section of circles is what I meant to ask

waxen creek
#

?
@viscid thistle @marsh crag

viscid thistle
#

it's still very vague

waxen creek
#

WE found a MATH GORILLA

#

OMG

#

YESS

#

HI

marsh crag
#

OMG

viscid thistle
#

yo

marsh crag
#

YO

#

You like maths?

viscid thistle
marsh crag
#

O damn

quaint mason
#

im confused on what it means by smaller and larger values

viscid thistle
#

n < your number < n + 1

quartz oxide
#

can someone help

quaint mason
#

@viscid thistle wait so

#

what is n??

viscid thistle
#

An integer

quaint mason
#

um

viscid thistle
#

Do you even understand the problem?

quaint mason
#

ah i got it

#

log4 (1/50) which is 1/50=4^y

#

=.02=4^y

#

solve for y for where .02 is between the values

#

ty @viscid thistle

#

i have a question, in that case, what happens if you do not have a base? @viscid thistle

viscid thistle
#

Wdym?

quaint mason
#

so one of the question asked the same thing but doesnt give a base

#

its just log(.009)

viscid thistle
#

It's probably either base 10 or e

quaint mason
#

is it usually just 10 by default?

uncut mulch
#

depends on context/whether the book has predefined the notation/level of math

quaint mason
#

i see

#

thank u

uncut mulch
#

at lower levels it's usually 10
as you get higher, e

quaint mason
#

aka 2.71

#

approx

loud marsh
#

wait should this go in trig

uncut mulch
#

there's a fine line between certain trig questions and pre-calc

#

so its ok

#

what have you tried?

viscid thistle
#

Are we assuming he's asking to prove it?

uncut mulch
#

yes

viscid thistle
#

Lol alr

uncut mulch
#

you could do:
$$LHS = \br{\frac{\tan(x) + \tan(y)}{\cot(x) + \cot(y)} \cdot \frac{1}{\tan(x)\tan(y)}} \cdot \tan(x)\tan(y)$$

obsidian monolithBOT
viscid thistle
#

@loud marsh ^

uncut mulch
#

and the problem reduces to simplifying the stuff in the big set of PARENS to 1

#

technically not mixing sides 😄

novel pecan
#

Y'all are smart asf wtf

torn seal
#

Helloo Im new to this server and I was wondering if someone could help me out

#

for my first question Id just like to check my work

#

Question: Find the Inverse of f(x)=2x^3+1.

#

My answer: f(x)=2x^3+1
y=2x^3+1
x=2y^3+1
x+1= 2y^3
y= x+1/-4
f^-1(x) x+1/-4

echo pelican
#

@torn seal

torn seal
#

Ohhhhh- Im so bad at thisss

#

Thank you for that.. @echo pelican

echo pelican
#

Yw good luck with the other problems

torn seal
#

thank you

#

Can you maybe show me how to solve something like this

echo pelican
#

Yes hold on

#

Im assuming when they right fg

They mean f of g of x

torn seal
#

basically f times g

echo pelican
#

For this composition of functions its like function done to a function

#

fg

Means do to g(x) what f says

#

So replace the x in f(x) with whatever g(x) is

#

@torn seal

#

Then wherever x appears in f you are instead replacing it with g(x)

torn seal
#

Ohh you're really smart, hopefuly Ill understand this. SO basically you just replace f and g

echo pelican
#

If its

fg

That is saying

Go into f(x) and wherever x appears we are going to instead replace it with g(x)

#

If i said gf it would be the other way around

torn seal
#

That makes so much more sense actually

echo pelican
#

We can do even

F(g(h(x)))

#

3, 4, 5 composition of any number of functions

#

The inner most one gets done first and you work your way outward to the outside most

torn seal
#

wait Im talking about the product

echo pelican
#

I am 90% sure that fg notation is composition

#

If it means multiply f and g

#

It would be like this:

torn seal
#

ive gotten this f(x) = 2x - 5
g(x) = 2 - x

(2x - 5)(2 - x)
4x - 2x^2 - 10 + 5x
-2x^2 + 9x - 10

echo pelican
#

Yeag

#

Perfect

#

Check about the notation with your prof

#

To be sure

torn seal
#

yay thank you

#

Im sorry if Im bothering you but is it okay if I ask another question..?

echo pelican
#

Lol go ahead

#

It doesnt hurt to ask

torn seal
#

aw thank you so much

echo pelican
#

Ok for this one

#

P gets you pound of apples

#

C gets you cost if you already know pounds

#

So you can do a composition of functions that will get you

Cost of P pounds

#

C will be the outside function since Pounds needs to be inside of the cost function

#

Similar to the first way i showed you the fg problem

#

Basically you want

C of P

#

This will get you your cost in terms of hours

#

Then you can substitute 32 in for h

#

Just @ me if you have trouble

#

@torn seal

torn seal
#

how does this look

#

P(n) = 375(32)
P(n) = 12,000

C(n) = 0.35(12,000) + 1000

cost of operating the cannery for 32 hours: $5,200.00

echo pelican
#

Yeah that seems about right

#

Good stuff

torn seal
#

:)

sand prairie
#

i dont know where to really put this nor do i know if im allowed to ask for ideas but can anyone help me with ideas of fractal art

solar cradle
#

sierpinski triangle, menger sponge, the dragon fractal

#

hilbert's curve

sand prairie
#

sry for not responding, but I want to draw something that isn't one of those

#

i have no ideas

solar cradle
#

You can come up with your own fractals then

#

you can do it with any arbitrary recursive pattern

craggy hamlet
#

Can someone give me a short definition of cosine? thank you

#

*and explanation

solar cradle
#

Imagine a right triangle, with one of the (non-right) angles as being x

#

The cosine of x is the ratio of the length of the adjacent side to the length of the longest side

#

The longest side is also known as the hypotenuse

craggy hamlet
#

ok thanks. then what is tangent then

sand prairie
#

do you think a simple pyramid/triangle with increasing blocks per layer work

#

im really overthinking this

solar cradle
#

ok thanks. then what is tangent then
@craggy hamlet the opposite side over the adjacent side

#

do you think a simple pyramid/triangle with increasing blocks per layer work
@sand prairie not really a fractal then

sand prairie
#

wait, im confused again xD

#

oh

#

its not repeating

viscid thistle
#

i need help with basic calculus

willow bear
#

@viscid thistle ok do you have a problem youre doing rn?

#

...

viscid thistle
#

yes

#

sorry

#

had to go to toilet

#

whats the derivative of

#

(x^2+k^2)^-3/2

#

does power rule applies over function ??? i learnt it only applies over x not like (x+k) k is constant

#

@willow bear

willow bear
#

have you heard of the chain rule?

viscid thistle
#

yes

#

ik it

willow bear
#

cause that's what you're gonna need in order to differentiate this

#

$\dv{x} (x^2 + k^2)^{-3/2} = -3x (x^2 + k^2)^{-5/2}$ is what it's gonna work out to.

obsidian monolithBOT
viscid thistle
#

WHAT

#

the heck

#

-3x

willow bear
#

ok can you show me the chain rule as it's stated in your textbook

#

so that i don't confuse you with notation you're not familiar with

viscid thistle
#

where did that -3x jumped from

#

shouldnt it be

#

-3/2

#

power rule

willow bear
#

-3/2 from differentiating the outer function, 2x from differentiating the inner

viscid thistle
#

u performed 2 steps

#

wait there is an inner and an outer function ?

willow bear
#

yes? (x^2 + k^2)^{-3/2} is a composition of two functions

#

it's f(g(x)) where f(t) = t^(-3/2) and g(x) = x^2+k^2

viscid thistle
#

OH MY GOD

#

you considered that power as a function

#

while i thought its the power in power rules and i can bring it down and thats it the derivative

#

wont that work ?

willow bear
#

the power rule technically only applies to functions of the form x^p

viscid thistle
#

ok

willow bear
#

it can also apply to (x+k)^p because technically you need the chain rule here but the derivative of (x+k) is 1 so it's ok

#

but if it's (something more complicated)^p you will need the chain rule and it'll give you a factor that you can't ignore

viscid thistle
#

no it doesnt applies here

#

you wrote -3x

#

while power rule

#

-3/2

willow bear
#

no, i am not using the product rule here

#

no it doesnt applies here
what doesn't apply

viscid thistle
#

power rule doesnt apply here

#

you just jumped 3 not 3/2

#

and u wrote an x there

#

power rule should have given -3/2

trim hemlock
#

Yes, it did

willow bear
#

-3/2 from differentiating the outer function, 2x from differentiating the inner

trim hemlock
#

But the chain rule also wants to join in

willow bear
#

did you like... read what i said, cause i thought i explained clearly what came from where

#

i can do it in more detail if you want

#

also you still havent shown me what notation you use for the chain rule. what does it take to get a simple answer to a simple question out of you?

viscid thistle
#

left d(right) + right d (left)

#

what i am asking is you cant apply power rule in (X+k)^p

#

you have to consider it a composite function

trim hemlock
#

I think you should reread what ann said

willow bear
#

yeah

#

cause it feels like you're flat out refusing to do that

#

also i said CHAIN rule not product rule

viscid thistle
#

fog =(f’ o g) × g’

willow bear
#

okay.

#

f(g(x)) where f(t) = t^(-3/2) and g(x) = x^2+k^2
your function is this

#

f'(t) = -3/2 t^(-5/2)

#

g'(x) = 2x

#

(f' o g)(x) = -3/2 (x^2+k^2)^(-5/2)

viscid thistle
#

this is so hard to imagine

#

but i learned it nvm

#

thanks

trim hemlock
#

fog =(f’ o g) × g’
Try not to use this notation

#

It can get very confusing sometimes

viscid thistle
#

when i saw this function

#

i thought that

willow bear
#

(f o g)' on the left hand side.

viscid thistle
#

-3/2 will jump down and -5/2 remains at top thats it the answer inside bracket remains unchanged

trim hemlock
#

What?

viscid thistle
#

but as he said

#

it the power rule only works for x^p

#

not for (x+k)^p

#

so i get the point

trim hemlock
#

No, the power rule, or any rule, works for all of the function

#

Not just x or any variable alone

#

But then you have to also remember the chain rule

#

Chain rule is very important

viscid thistle
#

then the answer should be -3/2(x+k)^5/2

#

if the power rule works then that should be answer

trim hemlock
#

But where is your chain rule?

#

And also thats not correctly derived

#

The outtermost function is not derived properly

viscid thistle
#

chain rule isnt used in power rule what i have learnt is that power rules says ( jump the power and subtract the power 1 )

trim hemlock
#

Nah, chain rule is used everywhere

viscid thistle
#

please kill me

trim hemlock
#

You just dont see it in functions like x^2

viscid thistle
#

but its the same here

trim hemlock
#

Its confusing at first, just do more exercises

viscid thistle
#

its just that

#

instead of x there is (x+k)

#

me poor physics guy

#

: (

#

the question asks me to calculate maxima

#

me dont know diffrentiation

#

me dead

trim hemlock
#

Well if it doesnt specify which method to use, you could solve it in other ways

viscid thistle
#

ur talk doesnt make sense

#

chain rule isnt used in power rule

#

they are diffrent rules

trim hemlock
#

Ehhh, lets try this f(g(x)) = x^2, g(x) = x, then f'(g(x)) = 2x.g'(x)

#

And g'(x) is 1 isnt it

#

Hmmm

#

But that is too complicated tho, so why not just write f(x) = x^2 and f'(x) = 2x by this rule called power rule

#

As i said, chain rule is everywhere

viscid thistle
#

ok

#

i learned

#

forget logic

#

can you find maxima of this

#

kqz/(z^2+r^2)^3/2

#

z is variable

trim hemlock
#

No, unless you specify what the output and input in as well as what all of that letters mean

viscid thistle
#

they are constants

#

z ranges from 0 to infinity

#

its a odd function

trim hemlock
#

Well then firstly use your quotient rule and then apply the chain rule afterwards

#

Do it slowly

#

As to not cause any confusion

viscid thistle
#

ok

#

is quotient rule derived from product rule ??

trim hemlock
#

Yep

past meadow
#

it certainly can be

#

you'll need chain rule too though

viscid thistle
#

Well then firstly use your quotient rule and then apply the chain rule afterwards

#

wont it make double diffrentiation

trim hemlock
#

Please not

#

And only apply the chain rule to the part where you differentiate a composite function

#

Or more specifically, (z^2 + r^2)^(3/2)

viscid thistle
#

first i used quotient rule

#

i got the expression

#

now its already diffrenciated 1 time

trim hemlock
#

Can you show it?

viscid thistle
#

i dont know how to use texit bot

trim hemlock
#

No need

past meadow
#

take a picture

trim hemlock
#

Use a camera

viscid thistle
#

=0

trim hemlock
#

I think we arent doing the same function, can you post the original function?

viscid thistle
#

yes we arent

trim hemlock
#

kqz/(z^2+r^2)^3/2
So you are telling me we arent differentiating this?

viscid thistle
trim hemlock
#

Ok then, why is x present in your derivative?

#

There is no x in the original function

viscid thistle
#

its multipication sign

#

XD

#

sorry

trim hemlock
#

Ok, next time use a dot, or dont use anything for multiplication sign

#

That can make a lot of people misunderstand

viscid thistle
#

my x are curvy

trim hemlock
#

Secondly, can you tell me the two functions we are using the quotient rule for?

viscid thistle
#

yes z and

trim hemlock
#

Curvy or not, it can be misinterpretated

viscid thistle
#

bottom

#

one

trim hemlock
#

So f(z) = kqz
g(z) = (z^2 + r^2)^(3/2)

viscid thistle
#

yes

trim hemlock
#

Do you agree?

#

Ok

#

So lets apply the quotient rule

#

The numerator is f'(z)g(z) - g'(z)f(z)

#

Right?

viscid thistle
#

yes

trim hemlock
#

so tell me what is f'(z)

viscid thistle
#

1

#

if u took constants out

trim hemlock
#

is it?

#

thats a bit odd

#

the rule states differently

#

so 1 is wrong

viscid thistle
#

its kq

trim hemlock
#

yes

#

exactly

#

and g(z)?

#

so f'(z)g(z) is?

viscid thistle
#

i did this thing and reached here

trim hemlock
#

no, just follow me

viscid thistle
#

ok

trim hemlock
#

what is f'(z)g(z)?

willow bear
#

but as he said
it the power rule only works for x^p
not for (x+k)^p

#

does that "he" refer to me

trim hemlock
#

probably the teacher

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nvm then

viscid thistle
#

kq(x^2+k^2)^3/2

trim hemlock
#

good

willow bear
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i'm not a he.

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idk why people keep pretending i'm a guy when i'm so clearly not

trim hemlock
#

ok now what is g'(z)

viscid thistle
#

its -3x(x^2+k^2)^-5/2

trim hemlock
#

what is x?

viscid thistle
#

x is z

trim hemlock
#

we are differentiating it with respect to z

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try not to change the variable

willow bear
#

gamer science, am i entitled to an acknowledgment that you fucked up

viscid thistle
#

yes from where have you gain such knowledge

trim hemlock
#

and also 3/2 - 1 is definitely not -5/2

viscid thistle
#

HBfasdufbsdibsdaiufbasdofndsnfhua

#

ok its

#

0.5

trim hemlock
#

and the derivative of x^2 is not 3x

#

i think im with ann on this......

viscid thistle
trim hemlock
#

but we arent differentiating from that

#

bruh

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did you really remember anything ann told you

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like i said, just do it slowly, and you wont get confused

willow bear
#

i can't even get them to answer the simplest questions i think they insist on not listening to me at all

viscid thistle
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i must not waste your time i am sorry i owe u a big time i m dumb

trim hemlock
#

d/dz[(z^2 + r^2)^(3/2) ] = 2z(z^2 + r^2)^(1/2).(3/2)

#

this should be g'(z)

stuck lark
#

@viscid thistle it was pointed out before. the main issue is you referred to her as “he”

willow bear
#

2z**^2**?

trim hemlock
#

wait oops

viscid thistle
#

@viscid thistle it was pointed out before. the main issue is you referred to her as “he”
@stuck lark so thats the main issu

willow bear
#

@viscid thistle it's not the main issue and it has nothing to do with the math, it just makes me really upset when people call me "he".

viscid thistle
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u hate bois

willow bear
#

?????

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bruh did you even read what i said

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or are you a gd misogynist

viscid thistle
#

yes i read

#

d/dz[(z^2 + r^2)^(3/2) ] = 2z(z^2 + r^2)^(1/2).(3/2)
@trim hemlock

#

yes

willow bear
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where did i say i "hate bois"

viscid thistle
#

u dont want urself to be called a boi

stuck lark
#

what logic is that

willow bear
#

yknow what i don't need to explain myself to someone so intentionally thick

viscid thistle
#

why siddhart and axazeel are spectators

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if u hate something u will hate called by that name

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simple logic

stuck lark
#

that was a rhetorical question

viscid thistle
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i am thick ?

willow bear
#

yes you are. you just committed the fallacy of the converse, too.