#precalculus

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winter comet
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but its relatively easy to understand

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of course the later stuff is probably much harder ๐Ÿ’€

chrome ether
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itโ€™s smooth sailing until you hit line/surface integrals which is not until late calc3

winter comet
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really?

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i thought calc 2 was harder than calc 3, and calc 4 was the hardest

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sorry uhh

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differential equations? is what im calling calc 4 idk ๐Ÿ’€

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thats what my brother said as difficulty for him

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but it could depend idk

chrome ether
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itโ€™s very dependent on how strong your algebra skills are

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bc late calc3 gets pretty computationally intensive

willow skiff
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Like once you get to Green's and Stokes' in multivar calc that's the end of the calculus sequence

winter comet
willow skiff
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I don't think differential equations should be part of the calculus sequence

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It's a subject in its own right

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Like you branch out into ODEs and PDEs

winter comet
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really?

willow skiff
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Like real analysis has calculus

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But it wouldn't make sense to include it there

winter comet
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i see your point ig...

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like

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it uses calculus

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but its a lot more...?

willow skiff
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Also apparently some unis only have Green's and Stokes in calc 4

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I take online courses at Indiana University East. The description of Calc 4 from their catalog is "Differential calculus of vector-valued functions, transformation of coordinates, change of variables in multiple integrals. Vector integral calculus: line integrals, Greenโ€™s theorem, surface integrals, Stokesโ€™s theorem. Applications."

winter comet
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i don't know much about calc 2,3,'4' lol

willow skiff
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As in they split calc 3 into two

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Weird

winter comet
willow skiff
winter comet
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hmm

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i mean

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from a dummy standpoint

willow skiff
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Yeah it's confusing when different unis call the same thing different names

winter comet
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multivariable calc sounds like implicit differentiation ๐Ÿคฃ and differential calculus seems like differentials (like dy = f'(x)dx)

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but i know its gotta be much more complicated than that lol

winter comet
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OHH u mean calc 3 is different

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i mean uhh

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multivariable calculus

willow skiff
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So like implicit differentiation involves functions of both x and y, f(x, y) = constant

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But you could also have f(x, y, z) = constant, of course

winter comet
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hmm

willow skiff
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And yeah a lot of the reasoning behind integration in higher dimensions is based on differentials, applied to different dimensions

winter comet
willow skiff
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Like the area element is now dx dy, and the volume element is dx dy dz

winter comet
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oh

viscid thistle
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The channel says 'pre-calculus', but I assume normal calculus is allowed here, yes?

willow bear
remote sable
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How do we do modelling with differentiation

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Is this why we say dy/dx = 0

sudden musk
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dy/dx represents slope, so dy/dx = 0 then the slope is 0

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dy/dx represents the slope of a plotted function*

remote sable
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Ahh that makes more sense now

sudden musk
remote sable
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Iโ€™ll show you when I get home

sudden musk
hexed apex
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You are walking away from a 4.2m tall lamp post, and you are 1.4m tall. Your shadow is increasing in length at a rate of 2km/hr. At what speed are you walking? Give your answer in km/hr

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is my work correct, if not please help

winter comet
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you wrote 1.2x instead of 1.4x once, but you fixed it after and i'm pretty sure the rest is correct

fiery creek
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@vernal swift here

vernal swift
opaque drift
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Iโ€˜d say itโ€™s B tell me if Iโ€™m wrong

vernal swift
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how do you come to the conclusion tho I just do not know the steps

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wait soning can i dm you?

opaque drift
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Sure

vernal swift
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alright

opaque drift
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@fiery creek is d correct?

fiery creek
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like vertical stretches, compressions,

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translations

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reflections

vernal swift
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Not really Iโ€™m not too familiar yet sorry ๐Ÿ˜ž

opaque drift
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Im sure he knows

winter comet
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you take the parent graph of 2sqrtx, translate it down 1 and left 3, so d is correct.

static cliff
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I was trying out fourier transforms and was having trouble, so I just winged it can got to this point

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It is pretty close but it is extremely overcomplicated

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It also overshoots by a lot

winter comet
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ngl i don't know why you had them there but just to make it look even closer you should remove the floors, max the r and zoom out and it looks perfect :D

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XD

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just keep zooming out...

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XD

vernal swift
fiery creek
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@vernal swift oh sorry

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i got distracted

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so what transformations are acting upon this function

vernal swift
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no problem ๐Ÿ˜…

fiery creek
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ok first of all

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I can't read your writing that well

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secondly

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i want you to follow a systematic process when you solve this problem

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let's starts with 2sqrt(x+3)-1

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what transformations are acting on this function

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look at A and C

vernal swift
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1 i got d

fiery creek
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those two graphs probably aren't the right answer

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why? because they're reflected

fiery creek
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the answer is d

vernal swift
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2 acd

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3 c

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4 d

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5 d

fiery creek
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ok it seems like you don't need my help

vernal swift
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is 6 d?

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i know its b or d

fiery creek
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you can verify these answers on desmos

vernal swift
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desmoos does not work for me unfortunately ๐Ÿ˜“

fiery creek
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why not

opaque drift
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Geogebra is a good alternative

tranquil jetty
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do u know about trigonometry

fiery creek
fiery creek
tranquil jetty
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anyone

fiery creek
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yeah I can help with trig

tranquil jetty
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i did

opaque drift
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Well, in terms of geometry or series?

tranquil jetty
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i have no idea

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whats the difference

fiery creek
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wdym desmos isn't telling you

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what is the function

warped cipher
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@vernal swift do you still need help?

vestal bison
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see as x increase y also increases right? so we eliminate A and C where the outcome decreases

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for the other 2, id say try the x values by logging them into the equation

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since ur not familiar with transformation

viscid thistle
runic turret
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so i'm in exponential equations and inequalities

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and the rule is to make the bases equal first

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but then the teacher gave an optional assignment to figure out how to solve ones where the bases aren't directly powers of a common number

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how in the world would you go about doing that HUH

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what kind of power can turn 2 into like 3 or something

summer ruin
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do you have a specific example

runic turret
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$2^{4x+1}=3^{x+2}$

obsidian monolithBOT
white stump
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Put both to the power of e^ln(

runic turret
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howd that help

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doesnt e^lnx just =x

white stump
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So you can get a common base of e, the ln has special properties where the linear function part will come out if the power and just multiply the 2 or the 3

runic turret
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shit wait a minute let me try

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so $e^{\ln{2^{4x+1}}}=e^{\ln{3^{x+2}}}$

obsidian monolithBOT
white stump
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Yes

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But ln(a^b) = bln(a)

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Then you can take the ln( on both sides to get rid of e then solve

runic turret
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$(4x+1)\ln{2}=(x+2)\ln{3}$ ?

obsidian monolithBOT
white stump
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Yes

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I would expand that

runic turret
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4x ln2 - x ln3 = 2 ln3 - ln2

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x(4ln2-ln3) = 2ln3-ln2

white stump
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Yup

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Unpleasant numbers but thats it

runic turret
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x=(2ln3-ln2)/(4ln2-ln3)

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dont the ln3-ln2 and ln2-ln3 cancel

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?

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theyre inverses

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ln3-ln2=-(ln2-ln3)

white stump
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?

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Oh

runic turret
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a-b = -(b-a)

white stump
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On the top there's a 2 and on the bottom a 4

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They're different numbers, your result is fine imo

runic turret
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right

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if it was 2(ln3-ln2) / 4(ln2-ln3)

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i could've

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but still

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thanks

white stump
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Np

runic turret
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wouldve been just -1/2

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damn that wouldve been so neat

white stump
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Math isn't always neat ๐Ÿคทโ€โ™‚๏ธ

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But when it is its cool

ashen hull
runic turret
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expand then like any other equation

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shove everything that isn't x to the right

ashen hull
runic turret
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the parenthesis

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multiply it out

ashen hull
white stump
runic turret
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(4x-1)ln2=(x+2)ln3

4xln2-ln2=xln3-2ln3

ashen hull
runic turret
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4xln2-xln3=ln2-2ln3

solar olive
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u can make it nice i guess

runic turret
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x(4ln2-ln3)=ln2-2ln3

solar olive
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by writing it as x = ln(9/2)/ln(16/3)

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i think thats more neat

runic turret
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whar?

white stump
ashen hull
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Ln2(4x)+Ln2=Ln3(x)+2Ln3

white stump
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Honestly that answer instead bad

runic turret
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how did u get x inside of the ln

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nvm i'm stupid

ashen hull
white stump
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?

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Isn't that bad*

ashen hull
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Ln2(4x)-Ln3(x)=2Ln3-Ln2
x(4Ln2-Ln3)=2Ln3-Ln2

white stump
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Yes

ashen hull
white stump
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Divide

ashen hull
summer ruin
runic turret
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yep i noticed

viscid thistle
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Logarithms should be appreciated more by the masses.

static cliff
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I tried out adjusting the shifting of the function to see if it could match better and got here

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I still need to fix the curves at 1 and 0

static cliff
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So I found this method on stack overflow I somehow it works

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I adjusted it and now when the sliders are set to max it matches the step function, it just does not work for negative values of x
But that can be fixed by just putting some negatives and adding it to the the below one

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The original one that I found was this

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Also, the adjusted version lags wayyy less than the other one I made

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I am pretty sure it works because the exponents make it sharper on the curves as the values get larger

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The only downside is that it goes crazy at small values of lowercase n and that it does not look as cool

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Also, this method is a little bit cheaty because it uses floor functions

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But it gives me an idea to include exponential function to my original desmos to get rid of the curve near 1 and 0

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Hopefully that method works

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This is the link to the stack overflow where I found the desmos

static cliff
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I adjusted it a little bit more and got the negative values of x also working

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I just made another function for the negative values of x and multiplied the two together

static cliff
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Okay

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After a lot of trial and error I was able to straighten the lines near y=0

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I did not use exponents the the stack overflow method

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Because it kept getting out of hand

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So I used absolute values

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I believe I can repeat the process for the curves near y=1

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Because the idea was that it essentially cancelled eachother out

static cliff
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I believe I have gotten close enough

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Finally

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After even more trial and error I was able to remove the curves by even more

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The only weird thing is that now the bottom is slightly more curved

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But this is wayyyy better than what I had this morning

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This is exciting

static cliff
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Now I don't have to zoom out @winter comet

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Hehehehe

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At least not as much

ebon ridge
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Hello everyone, I think my algebra skills are kind of lacking. Can someone show me or explain to me the step by step process of how the top expression simplifies to the bottom expression?

winter comet
ebon ridge
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Oh snap, I can't believe I didn't notice that

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Thanks for helping ๐Ÿ˜

winter comet
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wait nvm

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im just blind

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wait actually yeah that ones blank, not the ones before tho

winter comet
vast quartz
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wait omg

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i see it ๐Ÿ˜ญ

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i didnt notice the part where 2x was being added to Ax rather than multiplied

static cliff
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If you go to the bottom and click on the r slider and click enter

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Then close the new box

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I think it should fix itself

winter comet
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ab + cb = b(a+c)

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a = 2x, c = Ax, b = Ax

winter comet
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:<

static cliff
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Hmmmm

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That is weird

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Try this link

vast wind
unique salmon
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Guys, isn't integration just the function expanding its domain๐Ÿ˜ƒ

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(JJK reference)

winter comet
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integration just a function's domain expansion ๐Ÿ˜Ž 100%

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๐Ÿ’€๐Ÿ’€

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yk what nvm its actually funny ๐Ÿ’€

winter comet
random zephyr
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is there a simple to understand guide for calculus

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cause i am LOST

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what does f mean?

random zephyr
winter comet
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nah jk

winter comet
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i dont blame ppl getting confuseed

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its not actually that hard, i think

random zephyr
winter comet
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i mean like

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textbooks and stuff

random zephyr
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yeah too cluttered

winter comet
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yeah

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they use random variables for random things and it just doesn't give me a good idea of what the subject is about

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heck i was getting confused reading a section on stuff i already know lol

random zephyr
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one of the most confusing subjects has to be calculus

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my brain cant comprehend text

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i need to reverse engineer

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can i reverse engineer calculus?

unique salmon
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Guys calculus makes no sense to me

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But I understand how to do it

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Like I know how to differentiate equations, implicit differentiation, integration yadayadyada but I don't get what's it's for

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How it's derived etc.

winter comet
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idk

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like if they dont have a working way to learn it, its much harder to learn

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like i can read textbooks sure, but its very slow because it makes me overcomplicate things

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actually talking about it with people (or with myself) makes me understand it more

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teachers are sometimes helpful, videos are sometimes helpful

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sometimes not tho

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depends on how good the teachers/videos are :l

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everything depends lol

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i think its hard to learn, but not hard to understand

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of course i haven't completed it so i can't talk but at the same time i think i get the idea so maybe i can ๐Ÿซ 

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just my pov

ebon ridge
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I agree. Trying out different resources will help a lot. I also ask the question, "why?" A lot when I am studying. I always question my own assumptions, "why did I make that assumption?" "Why does this matter? How did this concept come about?" Etc, etc. Critical thinking comes from a lot of experimentation and curiousity. By understanding what a concept is, you can understand the components to this concept better

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Relating equations to the very essence of a concept is very powerful

winter comet
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yeah

lyric meadow
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iโ€™ll say them maybe later or maybe tomorrow

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iโ€™m tired rn

stuck valley
random zephyr
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4รท2(3)

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The correct answer is 4/6?

vapid plaza
willow bear
split pelican
willow bear
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i mean proper typeset fractions

split pelican
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Ah

willow bear
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$\frac{4}{2 \times 3}$ vs. $\frac{4}{2} \times 3$

obsidian monolithBOT
willow bear
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and in plaintext you should also write 4/(2 * 3) vs. (4/2) * 3 ideally, though 4/2 * 3 i personally would read as the latter

split pelican
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Yeah

random zephyr
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But some dude on tiktok live gave an example like that

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He dick fr

willow bear
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tiktok
math

random zephyr
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Calm down

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I was curious

dense eagle
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btw, is this kind of notation also ambiguous? like is it clear that its not (sin(\omega) )* t

hallow tide
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nobody ever writes that to mean sin(omega) * t

spring kettle
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Are matrices precalc

hallow tide
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they're covered in some pre-calculus courses yeah

spring kettle
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๐Ÿ˜ข

willow bear
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but you should write $y = A \sin(\omega t)$ anyway

obsidian monolithBOT
willow bear
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if only because that stops people tripping up

sudden musk
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or they will write y = A * t * sin(omega)

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to avoid confusion

zenith river
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proving lagrange remainder ( taylor polynomial ) , i dont understand how he got F'(si ) = to that thing

zenith river
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ok

simple urchin
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I need to write a proof to show that a linear function guarantees an output for ever even number.

Like y=mx+b is true for all even numbers. Can anyone help me with writing such a proof?

willow bear
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"a linear function guarantees an output for every even number" sounds a bit strange

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@simple urchin can you post the original problem exactly as it was stated?

noble vessel
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How do I solve this?

vestal bison
deft turret
#

yall
my friend Erik
he is in 10th grade
and he likes a 9th GRADER
what yall think about it

cunning schooner
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its just a single year

chrome ether
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!redir

tender questBOT
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This channel is only for on-topic discussion. Please take casual conversation to #discussion or #chill.

chrome ether
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๐Ÿค“

cunning schooner
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this is me rn

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fucking 4 am

winter comet
fading arch
noble vessel
obsidian monolithBOT
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Normed

noble vessel
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How does this help?

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I think we want equality here?

fading arch
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at the end you'll end up with an equality

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i already tried this problem and struggled, and the solution was to use a+b/2>=โˆšab

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at the end you find -1/2 for both

fading arch
noble vessel
fading arch
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sorry it's backward

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but you end up with this and then have to use a trick to make the 1/4 into a 1

fading arch
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you add 1/4+1/4-1/2 on the exponent

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and 16^(-1/2)=1/4

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then you simplify both side by multiplying by 4

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do you just want the all answer ?

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i can just send it it's easyer

noble vessel
fading arch
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sorry its a little bit messy

noble vessel
tawdry anchor
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Hello can anyone help me with this. I can only get the apparent power but i dont how to get the true power when only the voltage and current are given in a waveform. The apparent power is 2080 by multiplying the voltage and current by .707 to get the effective value but i dont know how to get the true power from.there. please help.

winter comet
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i know this is random, but does anyone have any tips for drawing graphs with only a pencil

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cuz

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i absolutely suck

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my intervals are not consistent, my lines aren't straight, ect. lol

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seems like a drawing skill issue ngl

willow bear
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are you using grid paper?

winter comet
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no

random yoke
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are you using a ruler

winter comet
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no

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i mean like i can

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it just seems like i should be able to make one in some way without pulling out a ruler

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accurate enough so that i dont make mistakes

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guess not tho ;-;

willow bear
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so maybe start using it.

plush terrace
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i need help with homework

chrome ether
#

!da2a

tender questBOT
#

No need to ask โ€œCan I askโ€ฆ?โ€ or โ€œDoes anyone know aboutโ€ฆ?โ€โ€”itโ€™s faster for everyone if you just ask your question! See https://dontasktoask.com/

tawdry anchor
#

Does anyone know how to solve inductive reactance. I need your help

chrome ether
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you'd be better off asking this in a physics server, check #old-network for the link

clever elk
#

Hey, I have a super simple question regarding derivatives.
Doing a derivative of b^x with respect to x, can also be written as ln(b^(b^x)), rather than (b^x) * ln(b). I've been told that it's not correct to do this, which is weird, given that i've just used the power rule of logarithms to rewrite it.
Why is ln(b^(b^x)) not correct?

summer ruin
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because it's equal to ln(b) * b^x which is not equal to b^x

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unless b = e

clever elk
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ln(b^a) = a*ln(b)?

summer ruin
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yes

clever elk
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I'm arguing for ln(b^(b^x)) being more true than (b^x) * ln(b), given that b = 0 is allowed in ln(b^(b^x)) but not in (b^x) * ln(b).

d/dx (0^x) is

summer ruin
#

you're already trying to say something about an ill-defined concept and asking why stuff you do is incorrect?

clever elk
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I've been told that im incorrect

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But not why i'm incorrect

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so I've come here to ask why I'm incorrect

summer ruin
#

yes because b^x cannot be rewritten as ln(b^(b^x))

summer ruin
clever elk
#

What do you mean? I'm not following you?

summer ruin
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,w plot 2^x and ln(2^(2^x)) from 0 to 1

obsidian monolithBOT
clever elk
#

Huh? 2^x can not be rewritten as log(2^(2^x)), but d/dx (2^x) can

summer ruin
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of course, since they're different functions

clever elk
#

Yeah, so what are you proving here?

summer ruin
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it seemed like you were talking about b^x being the same as ln(b^(b^x))

clever elk
#

Where did I write that? can you please quote it?

summer ruin
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in your very first comment

clever elk
#

Ah, do you mean:

compact spade
#

Need help on these two problems

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87 & 114. 88 not necessary

willow bear
#

@compact spade have you made any progress on #87?

compact spade
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Nope

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Don't even know how to start

willow bear
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ok, let's see...

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do you notice anything special about your points?

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specifically, the first and the third points -- (0, 0) and (4, 0)?

compact spade
#

Yep, reflected evenly across x = 2

willow bear
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not what im looking for.

compact spade
#

Ah

willow bear
#

the points themselves.

compact spade
#

X intercepts

willow bear
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yes, they are the x-intercepts.

compact spade
#

Ahh ok

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Oh shit ok I think I got it

willow bear
#

does this enable you to continue?

compact spade
#

Ty

willow bear
#

ok great

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on to 114?

compact spade
#

Yes please :)

willow bear
#

any progress with that one?

compact spade
#

No, none yet

willow bear
#

do you know what partial fraction decomposition means?

compact spade
#

Kind of?

willow bear
#

there's no kind of, you either do or you don't

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regardless of whether you know how to find one

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im asking if you know what a pfd is

compact spade
#

I'm gonna go with no

willow bear
#

give this a watch

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then come back to that problem

compact spade
#

Got it, will do

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Thank you so much for your help btw, really really appreciate it

unique salmon
#

Yall ever just do a math question and think about why you need it

clever elk
#

yeah

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I never really understood why I would need to know geometry-constraint questions until I worked with CAD

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..or calculus and linear algebra questions until I worked with machine-learning

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and I suck at it. But just having some base understanding of how one can interprete equations in natural language is super useful

tender mist
unique salmon
#

Anyone know what kinda math you need for computer science?

tawdry anchor
unique salmon
unique salmon
#

This is physics

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Recommended the physics and engineering server

tender mist
#

Join the server called "1 server is unavailable due to a temporary outage"

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That should help with your physics problem

willow bear
#

if someone said something in violation of the rules, take that to @tall sequoia's DMs

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or ping moderators with a link to the offending message

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...

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i mean, i saw that

zealous mango
#

can someone pls help me ๐Ÿ˜ข

crisp timber
#

Interesting. Its a bit tedious to me since I don't take trig class, but let me see.

jolly wind
#

pretty easy stuff

vestal bison
#

i dont understand this question and solution at all. you see at the end it says real coefficients and complex coefficients in two questions? both of them got the same coefficients which is 1

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and like whats linear factors

summer ruin
summer ruin
#

it says coefficients of linear factors, not coefficients of P

vestal bison
summer ruin
#

depends on the field you're considering

vestal bison
vestal bison
#

or (x-3)?

summer ruin
#

yes

vestal bison
#

so anything is a linear factor basically?

summer ruin
#

coefficients of a polynomial ax^2 + bx + c are a,b,c

summer ruin
#

x^2 + 4 is not a linear factor

nocturne wigeon
#

Anyone here help me with a quick trig questions littery 10 seconds

vestal bison
#

or any powers in general?

summer ruin
#

it's not a linear polynomial

vestal bison
vestal bison
summer ruin
#

a polynomial of the form ax+b

nocturne wigeon
vestal bison
#

like as i said x-โˆš2 etc

summer ruin
#

yes

vestal bison
#

i got the linear part but i still dont get how 2i can be a coefficient

#

all the x values i see got 1

summer ruin
vestal bison
#

and i is not an unknown

vestal bison
#

okay

summer ruin
#

x-2i is a linear polynomial with complex coefficients

#

1 and -2i

vestal bison
#

like 3x^2 + 5x -5

but 5 has unseen x^0 right

#

so basically its a coefficient as well

vestal bison
#

what about the irreducible quadratic factors?

summer ruin
#

they cannot be factored into linear terms over field R

#

but it is possible over complex numbers

#

as seen in the solution

vestal bison
summer ruin
#

it is real

willow skiff
#

Even if all the coefficients of the original polynomial are real

vestal bison
#

i lost all my knowledge in math tbh i guess need to start w numbers

summer ruin
#

it does? the polynomial has both (x-sqrt(2)) and (x+sqrt(2)) factors

willow skiff
#

Knowing the different types of numbers

vestal bison
#

oh okay okay nah i know these

#

i misunderstood the thing with complex and yk

willow skiff
#

Yeah so just refresh your memory so that you can apply this knowledge to other situations

vestal bison
#

complex is just the imaginary ones

willow skiff
#

Which is beyond your level

willow skiff
#

A lot of people tend to mix up 'complex' and 'imaginary': it's no big deal actually

#

imaginary technically means like 2i, 3i, -sqrt(2)i, pi * i

#

And not a + bi

#

And there's more than one definition ofc

vestal bison
willow skiff
#

It has roots x = 2i and x = -2i

vestal bison
#

we didnt use i because it asks for real ones

#

right

vestal bison
vestal bison
#

alright thank you

willow skiff
#

No worries

vestal bison
#

i got one more question, so is the statement "every polynomial has at least one real zero" is incorrect right?

#

also uhm i got this polynomil i tried rrt but it didnt work so i guess this doesnt have any real zeros and how do i factorize this and find the complex zeros?

#

$$x^4+2x^2+1$$

obsidian monolithBOT
#

ghiolimer

vestal bison
#

i usually use desmos but i dont wanna use it 24/7 bc i need to learn this thing

summer ruin
#

ah nvm I interpreted the question differently

#

but yeah it is incorrect

vestal bison
#

okay

#

how do i find zeros the polynomial above

#

oh okay

#

i got it

#

okay nvm

summer ruin
#

it is quadratic in x^2

vestal bison
#

i did it

#

lol yea

#

still, thanks

vestal bison
# summer ruin depends on which field you consider

i have another question regarding this. you see a polynomial with a degree 3 has 3 roots whether real or imaginary. but u see sometimes these roots have multiplicity. do they also count as roots again? or n=3 means the polynomial has 3 different roots

#

for example i got a polynomial here i factored it and got

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

obsidian monolithBOT
#

ghiolimer

vestal bison
#

it has -2, -2, and 2

#

so i guess -2 counts twice right?

#

otherwise we would have -2 and 2 and we would have one left and imaginary roots come as couples

#

am i right

primal tusk
#

Ohhh precal

primal tusk
#

If thats the case then it becomes x=2

compact spade
#

I could solve this normally, but not with the method it wants me to use

summer ruin
#

what do you consider to be "normal" method?

compact spade
#

Add row 1 to row 2, get value of x. Add row 2 to row 3, plug in value of x to solve equation for y. Then plug in both values to any of the three equations to solve for z.

summer ruin
#

this is gauss-jordan elimination

compact spade
#

Oh lmao alright

#

Thank you

half pollen
#

can you help me with verifying something ๐Ÿ˜ญ please

#

Question:


1/a + 1/b = 3/2018```
#

Somebody mentioned:

1/a + 1/b = 3/2018
2018 can be prime factorized as 2 * 1009
Hence you rewrite as: 2 ร— 1009 ( a + b) = 3ab 

Now, at least one out of a and b must be divisible by 1009, so it's either:
1) Both
2) One( a) 
3) One (b)
Each will give you 2 ordered pairs 
So 6 possible pairs
#

But this is wrong reasoning right? ab can't both be divisible by 1009

#

unless he assumes that gcd(3, 2(a+b)) = 1?

summer ruin
#

I know zero number theorycatthimc

half pollen
#

i know 0 number theory too

#

๐Ÿ˜ญ

#

okay thanks np

compact spade
#

Ok last one

#

I mean, for today

#

There will certainly be more

summer ruin
#

if the parabola passes through points (x,y), then these points must satisfy the equation of parabola

half pollen
#

bruh

half pollen
#

you can have three equations right for the three unknowns?

summer ruin
#

well write it down then

half pollen
#

Lol

limpid wasp
half pollen
#

yes they've been told that twice

compact spade
#

Wait no I think I get it

#

Ok ty

half pollen
#

you'll have three equations in three unknowns

#

they you use gaussian elimination to get the unique values of a,b, and c

elfin anvil
#

If z = r cis ฮธ, and -ฯ€ < ฮธ < -ฯ€/2, is it right or wrong that โˆšz = โˆšr cis (ฮธ/2)?

#

(sorry I don't know how to type cis in latex, or to format fractions in parentheses)

winter comet
#

you mean when finding the roots of z?

#

this is more accurate

#

i think ^

#

oh wait yeah thats what you said ๐Ÿ’€

proven void
#

how to get better at math

winter comet
#

very broad

#

two step process

#

๐Ÿ’€

proven void
#

I need help with math, can someone help

willow bear
#

and "i need help with math" is like

#

the vaguest possible request

proven void
#

its something related to symmetrical points I dont understand

willow bear
#

otherwise clarify what you don't understand here

#
  • symmetry wrt a line means mirror reflection across that line
  • symmetry wrt a point means a rotation by 180 degrees around that point
proven void
#

what would be line symmetry of (1;3) wrt y-axis/line

#

what is this?

willow bear
#

a formula that

  • computes a point symmetry, not a line symmetry
  • is way over-caliber for your problem
willow bear
#

here is the point (1, 3)

#

mark on this picture where the point (1, 3) will go when mirrored across the y (vertical) axis.

proven void
#

(-1;3)

willow bear
#

it is like a miracle that you are now able to answer your own question.

proven void
#

what about x axus

willow bear
#

mark on this picture where the point (1, 3) will go when mirrored across the x (horizontal) axis.

#

or somehow end up telling me its coordinates.

proven void
#

(1;-3)

willow bear
#

so (1, 3) will stay in place?

#

that's more like it...

proven void
#

im new

#

what about wrt origin

willow bear
#

well,

#

mark on the picture where the point (1, 3) will go when rotated 180ยฐ (half of a full revolution) around the origin.

proven void
#

(-1; -3)

#

ty!

willow bear
#

i did precisely nothing

#

except stick your nose in the problem, and some key words, a bunch of times

#

all of this you were surely able to do on your own

proven void
#

sorry.

willow bear
#

i am neither demanding nor expecting an apology

proven void
#

why so serious today ann

#

alright.

willow bear
proven void
#

how to tackle

willow bear
#

do you know what an increasing function looks like, graphically?

proven void
#

with a positive slope ferrisCat

willow bear
#

ok

#

do you know what a maximum or minimum value looks like graphically?

proven void
#

I dont get it.

willow bear
#

you know the graphical meaning of supremum but not of maximum?

proven void
willow bear
#

i literally tried taking you step by step through the things you needed to take note of

#

your response was to completely defenestrate all that and (implicitly) call for somebody else

proven void
#

I dont know how min max works

willow bear
#

defenestrate means to throw out the window

willow bear
#

โŒ

willow bear
#

you should do your own research on this topic. read your notes, read your textbook, watch khanacademy or ochem tutor

#

theres so much out there

#

put some effort in, lmao

proven void
#

I just started this class today ngl I might have already gone too far ahead of myself

#

I think this is going to be seen next week

willow bear
#

what class is this

proven void
#

pre university real anal

runic turret
#

how would i use the base change formula here

#

"solve $2^{\log_3 5} * 5^{\log_3 31,5} * 7^{\log_3 0,6}$"

obsidian monolithBOT
fiery fable
#

hi can someone please explain where he got x-4 from?

#

this is adding rational expressions

willow bear
#

,rccw

obsidian monolithBOT
willow bear
#

what was the original problem?

#

@fiery fable

fiery fable
willow bear
#

,rccw

obsidian monolithBOT
willow bear
#

hi can someone please explain where he got x-4 from?

so then x-4 is part of the original problem, isn't it?

fiery fable
#

oh

#

sorry

#

thank you

lofty geyser
#

Help with polygons

willow bear
#

ok let's just cut away the black bands that are 2x as tall as the image itself

#

@lofty geyser progress so far?

lofty geyser
#

what are black bands

#

oh

#

Uhh so far I found c d f e are part of a heptagon

#

Right?

willow bear
#

sure

#

anything else?

lofty geyser
#

Nope

#

Still confused on how to do it

willow bear
#

ok, let's start simple

#

do you know how to find the sum of the angles in a simple (non-self-intersecting) polygon?

lofty geyser
#

The interior angles?

willow bear
#

yes, the interior angles.

lofty geyser
#

is the answer 745.7

willow bear
#

how did you get this?

rancid bramble
#

hi

#

is it true i dont need to study for unit 4

#

for the ap pre calc test

#

just 1,2 and 3

#

<@&286206848099549185>

opaque field
#

So I was about to screenshot my math problem, but then i see a notifacation

#

read it...

chrome ether
#

!redir

tender questBOT
#

This channel is only for on-topic discussion. Please take casual conversation to #discussion or #chill.

chrome ether
opaque field
#

I know

chrome ether
#

this does not merit a helper ping

opaque field
#

Im just saying

#

i was about to screenshot something

#

but then that came up

#

...

chrome ether
# chrome ether what

if you're trying to skimp and scrape by with a 5 maybe you can drop unit 4 if you can answer every unit 1-3 question correctly

#

but that's highly unlikely

#

so get studying on unit 4

viscid thistle
#

Would any of these chapters help with calculus?

dusky zenith
#

Does anyone have the AP precalc practice tests by college board? I canโ€™t seem to find them and apparently they have released some practice tests

winter comet
#

7.9 literally says differentiation

#

๐Ÿ’€

drowsy nova
#

drhgfds

proven void
#

how to find roots of 1/x

chrome ether
#

it has none

#

if by "roots" you mean "zeros"

split pelican
proven void
chrome ether
#

literally basic intuition?

#

if i divide something into lots of tiny pieces i can't ever make the size of any of those pieces zero

proven void
#

whatever

#

I was expecting something mind blowing but it isnt

willow bear
#

start with the equation 1/x = 0

#

multiply both sides by x

#

you get 1 = 0

proven void
#

I thought it was going to be something more involved, thanks.

jolly stump
chrome ether
#

npnp

white rapids
viscid thistle
#

Hello, I am a student in honors pre-calculus and scheduled to go into AP Calculus AB+BC next year. I am struggling with grasping this current level of trigonometry as a whole and wondering if anyone can give me some good ideas of where to start from the bottom-up so I can begin to comprehend it

wind jungle
#

Hi! I have no clue how to solve this problem. I keep getting

-x(-x+40)(x+5)

for factors, but I donโ€™t see how that would work as a solution for volume because of the negative coefficients.
Help much appreciated, thanks!

willow bear
#

-x(-x+40) = x(x-40)

#

on the other hand this problem is poorly stated bc it doesnt actually say anywhere that the other two dimensions can't be x^2-40x and 1

wind jungle
wind jungle
tired stone
#

ios this correct?

willow skiff
#

You should do $\log_a x = \frac{\log x}{\log a} \implies$ tho

obsidian monolithBOT
willow skiff
#

The arrow is used any time you want to connect two statements

#

But they aren't exactly equal to each other

hallow linden
#

I finally tried understanding euler's formula

#

Basically tried visualizing it myself using compound interest

barren jewel
#

HELP

#

I NEED HELP WITH INFINITE INTEGRALS AND LIMITS

willow bear
#
  1. WHY ARE YOU SHOUTING?
  2. THIS SOUNDS MORE LIKE A #calculus ISSUE!
  3. YOU MIGHT WANT TO ACTUALLY POST THE QUESTION(S) YOU NEED HELP WITH!
#

@barren jewel

barren jewel
#

I donโ€™t see it ๐Ÿ˜ฆ

willow bear
#

hm

#

oh this might be bc it's in the early university category

uncut mulch
#

you could also just claim your own personal channel

barren jewel
#

Hmm good idea!

#

Thx

winter comet
#

๐Ÿคฃ jk ๐Ÿ’€

half pollen
winter comet
#

nooooooo ๐Ÿ˜ญ

#

oops i talked in his server

#

twice

stable gull
#

mmm nah i claim this channel

#

talks tag is wild

#

i don yap that much do i ๐Ÿ˜ฆ

#

๐Ÿ˜ญ

river drift
#

the "talks" role says you want to be pinged when a lecture ("talk") is happening on the server. you chose this option in id:customize

sour oxide
full wing
#

lets see if you guys can solve:

#

pi=2ln(x)/x, solve for x

#

for anyone who doesn't know, a variable such as x can be any number

signal vault
#

Can someone tell me the difference between evaluate and differentiate with respect to x ? Both means same to me

willow bear
#

it sounds like the function written under "differentiate wrt x" was obtained by taking your thing and then differentiating it a 3rd time

willow bear
#

"differentiate" by itself does not mean "take the 3rd derivative"

#

just for the record

whole shoal
#

Help

peak token
#

how do i convert -7โˆš7 into an entire radical?

tender mist
# peak token how do i convert -7โˆš7 into an entire radical?

I don't think the negative can be put into it, but anything going into a square root (specifically square, not cube or higher), has to be multiplied in by the square of the term going in. So you want to multiply the 7 inside the radical by the square of the outside term (so the square of the 7)

surreal crescent
#

Why is it called precalc if calc introduces completely new topics that are different from anything before it? Why not just call it algebra 3 with a hint of geometry

river drift
#

because it's supposed to have all the topics required to prepare you for a calculus class

#

since calculus has a fair amount of prerequisite material

winter comet
#

it certainly uses the skills taught before it

#

it just has a few abstract concepts

#

but these concepts are built from facts you learn before so yeah...

#

for instance, calculus has derivatives. this is just the slope of a tangent line. slope is an algebra 1 concept i think, and if you didn't learn what a tangent line was in algebra 2 then you should have at least learned it in precalc before taking calc

#

because they kinda just do fancy stuff with tangent lines

#

thats the entire derivative part of calculus lol

#

tangent lines of graphs

near lintel
#

how can i do this?

willow bear
near lintel
willow bear
#

ok

#

what can you tell me about theta, given that the slopes of both ramps are 3/5?

compact spade
#

help

#

please

#

ah

surreal crescent
winter comet
#

im not going to lie

#

how about we call precalc algebra 3

#

and calculus algebra 4 ngl

#

calc 2 algebra 5

#

calc 3 algebra 6

#

THEN we ok

#

๐Ÿ‘

surreal crescent
#

Calc ainโ€™t really algebra

#

Moreโ€ฆ Infinite geometry

winter comet
#

...sure

#

i guess

#

i mean

#

its a graph

#

but i guess if ur taking the integral then yeah its infinite geometry

compact spade
# compact spade a

This is due tomorrow and I'm completely lost can I get some help on this really quick

winter comet
#

but the derivative is more like a graph

winter comet
unkempt cave
#

Can you go straight from honors geo to precalc with trig when the recommended middle class is algebra 2

compact spade
#

Wdym by proportional

winter comet
#

umm

compact spade
#

equivalent?

winter comet
#

when the matrices has the same dimensions

compact spade
#

yes

winter comet
#

and the elements are equivalent yeah

compact spade
#

yes

winter comet
#

so what are you stuck on

compact spade
#

wait i swear to god is that fucking it

#

is it that easy

winter comet
#

๐Ÿคฃ

#

yes

#

lol

compact spade
#

i

#

ok

winter comet
#

xD

compact spade
#

thank you

winter comet
#

๐Ÿ‘

compact spade
#

i will be back later ๐Ÿ’€

winter comet
#

bro was overcomplicating it

#

XD ok

surreal crescent
#

Wait now Iโ€™m confused, what the hell is z

winter comet
#

in that specific one there is no z

surreal crescent
#

Ye

winter comet
#

but i'm assuming it was referring to a set of problems

#

and some of them have x,y, and z

#

some of them have only x and y

#

ect

#

yeah it says problems 1-4

#

LOL

#

it says find x and y or x and y and z

#

lol

compact spade
#

ok no i am now actually lost

#

what the fuck is this shit

winter comet
#

those are 3 by 2 matrices

#

there is no x and y or z

compact spade
#

i noticed

winter comet
#

so um

#

are there more instructions?

#

or more part of the problem or something?

compact spade
willow bear
winter comet
willow bear
#

@compact spade do you know how to add matrices

#

it is actually dead simple

compact spade
#

on god?

winter comet
#

XD

#

yeah

compact spade
#

sorry im tired no shit was absolutely the wrong phrase

#

i am so sorry

#

that came off as REALLY mean i can barely think let alone type

winter comet
#

really?

#

i thought it was funny XD

willow bear
#

there are far meaner things you could have said

#

by several orders of magnitude

#

anyway

compact spade
winter comet
#

then you got a vector YAY

#

๐Ÿ’€

willow bear
#

addition, subtraction and scaling of matrices is just entrywise.

#

ie you add them entry by entry

compact spade
#

ok will get back to you

willow bear
#

like you would with vectors

compact spade
#

thank you

surreal crescent
#

Please, tell me when Iโ€™m going to stop dealing with graphs and actually do some fun stuff

surreal crescent
compact spade
#

like 1/3 of the way through

#

oh

winter comet
#

i mean

#

calculus is graphs

compact spade
#

i have had a different experience

winter comet
#

linear algebra is graphs

#

maybe not probability

compact spade
#

you go to triangles at some point though

surreal crescent
#

Iโ€™m on combining functions

compact spade
#

yeah you're like halfway out of graphs i think

winter comet
compact spade
#

for this year

winter comet
#

actually linear algebra is very weird graphs i think

#

i havent taken so i cant really say fs

#

but i'm very sure its got graphs ๐Ÿ’€

surreal crescent
#

Itโ€™s just algebra but with cubics ๐Ÿ˜ญ

winter comet
#

wdym cubics

#

you mean like three dimensions

#

or multiple dimensions

surreal crescent
#

No, like f(x) =x^3+x^2+x+3
G(x)= (2x^3+5x^2+x+2)/x+1)
Find (3(f/g))(x)

winter comet
#

um

#

would that be relatively basic linear algebra?

surreal crescent
#

Idfk, my state does stuff wierd, Iโ€™m in precalc honors rn

winter comet
#

huh

surreal crescent
#

In the middle of a unit on applications of functions, doing comic sections next

winter comet
#

conic sections?

#

comical sections xD

willow bear
surreal crescent
#

wtf, laws of sin and cos are on my silabuss

surreal crescent
winter comet
#

i didn't know if math subjects have strict definitions lol