#precalculus

1 messages · Page 263 of 1

opaque idol
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Ohhh I seee it now

quaint mason
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after u substitute 4 in for m, u get t

opaque idol
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And that will be the answer?

quaint mason
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t=.4m^2

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u know what m is already

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substitute that in

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and then solve for r by doing 150+4t

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plug t in

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and thats r

opaque idol
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I got 182

quaint mason
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mmm lemme see

opaque idol
#

Thank you I appreciate it

quaint mason
#

thats what i got

opaque idol
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Ok cool thank you

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Can you also help with this graph question

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?

quaint mason
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which

opaque idol
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A & B

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For number 6 it’s supposed to be (fo G)(-2)

random cloud
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Uhhh now what

quaint mason
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what fo again?

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tryna remember

random cloud
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You cant do difference of squares

opaque idol
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It’s saying F of G

quaint mason
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sorry gimme a sec

opaque idol
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Plus I also gotta find if the function is even,odd and neither

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Yeah it’s fine take ur time

quaint mason
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wait (fog)(-3)

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-3=x?

opaque idol
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No it’s -2

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It’s a typo

quaint mason
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oh

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f(g(-2))

opaque idol
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I think you can say that

quaint mason
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just havin problem solving for x or readin the graphs xD

proud raven
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@random cloud use a substitutiqn

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then do the cubic trick

opaque idol
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Yeah lol

proud raven
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same opposite always positive

quaint mason
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jan, how do u solve for x from Jpiggy picture

random cloud
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You mean say u=s^3?

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S^2 I mean

opaque idol
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If this helps on the left side on the bottom that line is g(x) and the top on is f(x)

proud raven
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wchich part?

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@random cloud s^3

random cloud
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You cant do sum of squares tho

proud raven
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oh wait

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yea

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(s^3)^3

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?

quaint mason
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^

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ye

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wait

random cloud
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Oh yeah

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I think lol

quaint mason
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exponents adds

proud raven
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i dont get the piggy questiqn what re you ask?ng

opaque idol
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Is the function even,odd or neither?

quaint mason
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from JPiggy ss, how do u solve for x again

proud raven
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oh

quaint mason
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so u know um

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f(x)

proud raven
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theres two functions graphed there

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?

random cloud
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Exponent raised by exponent is multiplicative

quaint mason
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yeah

opaque idol
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Yeah

random cloud
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Not additive

quaint mason
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oh my bad

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i thought that exponents are different when raised

random cloud
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Wait 2 times 3 is six

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You're right

quaint mason
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i thought it was additive vice versa for division and sub

random cloud
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Yooooo

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I ended up with (s^3 + 1)^2

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That's crazy

proud raven
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can always just expand and group to check

random cloud
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Shortcut time 😎 😎

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Yoooooo

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I end up with

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(s + 1)^4

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I feel like I did something wrong

quaint mason
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oof

random cloud
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So wait

quaint mason
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i did something and got s^12+1 insteaf

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lol

random cloud
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u=s^3

quaint mason
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but the idea is to have

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s+1

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maybe what u can do is

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(s+1)^9

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and then um

random cloud
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Cuz (s^3 + 1) = (s^2 - s + 1)(s + 1) which is just (s + 1)(s + 1) which is just (s + 1)^2

quaint mason
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i cant remember how but its like jan said, somethin to do w the cubic

random cloud
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I feel like I'm running in circles

quaint mason
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mmm

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(s+1)(s^4+1)^2?

random cloud
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Where did you get that

proud raven
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soap

quaint mason
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nope

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hmm

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is it?

random cloud
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Is this some paradox or something

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Fuck it I'm doing long division

quaint mason
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ye

random cloud
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S+1 is my divisor

quaint mason
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yes

random cloud
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Lol

proud raven
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(s+1)(s²-s+1)(s^6-s^3+1) is as far as i got

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im out of paper

random cloud
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s^36 + 1

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@proud raven wouldnt that simplify into:
(s+1)^2 (s^3+1)

proud raven
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,w factor x^9+1

obsidian monolithBOT
proud raven
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:p

random cloud
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Shouldn't you do something about that x^2 - x

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And x^6 - x^3

proud raven
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theres nothing else to do

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at least i wouldnt

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unless its asking for roots

random cloud
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But it's not completely simplified

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And if you do continue with this

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You get something weird

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Why is that

proud raven
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you just want nice factors

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no screwy irrational nonsense

random cloud
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But why does that happen when we keep going

proud raven
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mayyybe a fraction if it looks nice

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because the roots arent nice

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,w graph x^9+1

obsidian monolithBOT
proud raven
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lol

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,w 0=x^9+1

obsidian monolithBOT
proud raven
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yea

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fucked up roots

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other than the (s+1)

random cloud
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Ok cool

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That's weird

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So the right side is cursed

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But

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Why

proud raven
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?

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most numbers arent nice

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i guess

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most numbers are irrational iirc

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at least reals

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or something idk analysis

random cloud
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Noooo it happened again 😭

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The far right parenthesis turns into (r^3 + 1) and it will go on forever

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Wtf does that mean

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,w graph x^6-1

obsidian monolithBOT
random cloud
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This kinda annoys me wtf is going on

proud raven
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so uhh

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(r^3+1)(r^3-1)

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then each of those factor

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,w factor x^6-1

obsidian monolithBOT
random cloud
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Am I the only one that sees the paradox

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That it continues to go forever

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Whyyyyyyy

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And is there a rule that tells me to stop

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When this happens

proud raven
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what?

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what do you mean?

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you factor to linear, and quadratic terms

random cloud
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Look at (x^2 + x + 1)

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Waaaaait nvm I figured it out

astral mantle
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just expand out the equation

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to 6x^5/x^4 - 6x^4/x^4 - 3x^3/x^4

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then you can divide them all by x^4

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so you get 6x - 6 - 3/x

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and derive that

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i think you did it correctly you just did signs wrong @terse ravine

terse ravine
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I entered it as -3x^-2 - 6 and it was also wrong

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thats why I'm wondering why

astral mantle
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what about 3x^-2 + 6

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?

terse ravine
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Oh yea

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But first I am here.

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f'(x) = 6-3(-1)x^-2

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-3(-1)=3x^-2 ?

astral mantle
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what?

terse ravine
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I'm confused

astral mantle
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6 - (-3x^2)

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6 + 3x^2

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subtracting a negative is just addition

gritty axle
astral mantle
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did you try 2cos(2q)

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i think i already went over that one

terse ravine
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f'(x)=6-3(-1)x^-2

astral mantle
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what part of that is confusing

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3 * -1 = -3

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6 - (-3) = 6+3

terse ravine
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f'(x)=6-(-3)x^-2

astral mantle
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why do you just keep sending it over again]\

gritty axle
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youre right

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i had a negative instead of a positive

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thank you @astral mantle

terse ravine
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f'(x)=-3x^-2+6?

astral mantle
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yes

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glad you got it after i said the answer and explained it 3 times 🙂

gritty axle
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oops, im in the whole frong channel for this

astral mantle
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actually nvm its wrong still

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its 3x^-2+6

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not -

terse ravine
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x^-1-1 =x^-2

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not sure where you got the x^2

astral mantle
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thats what i meant

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sorry

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idk if you are trolling or not but gl im dippin

terse ravine
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nevermind I'll wait until I understand it completely.

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too many are talking at the same time..

cloud prism
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Well as a short summary: $$ (\frac{6x^5-6^4-3x^3}{x^4})' = (\frac {6x^5}{x^4} - \frac {6x^4}{x^4} - \frac {3x^3}{x^4})' = (6x)' -(6)' - (\frac 3 x)'$$

obsidian monolithBOT
terse ravine
cloud prism
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Well imagine that X

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:'D

terse ravine
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the constant cancels

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I'm left with (3/x^2)+6

cloud prism
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Yes. -(3/x)' = -( -1 * 3/x^2) = 3/x^2

fathom root
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hey could someone help me understand this answer

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Determine the value that the function f approaches as the magnitude of x increases.

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i see that the answer is 7 but im just a bit confused onto why that it is

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moreover what the question is asking

cloud prism
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So you're asking for $ \lim_{x\to\infty} 7 + \frac 1 {x-8}$ ?

obsidian monolithBOT
fathom root
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yes

cloud prism
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Well the first term doesnt depend on x so we can ignore that as it's constant. So we have 7 + $lim_{x\to\infty} \frac 1 {x-8}$
Well and that approaches 0

obsidian monolithBOT
fathom root
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wait so i wanna ask first though is the question essentially asking for the horizontal asymptote of the function?

cloud prism
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Yes

fathom root
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so are you just doing 7(x-8)/x-8 and getting 7?

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srry btw idk how to use the bot

cloud prism
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I didn't go over this with that rationale, I think: if x gets larger and larger 1/(x-8) get's smaller and smaller but never reaches 0

fathom root
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ohh i see

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that makes sense

cloud prism
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even if it would reach 0, it just never gets away from it again

fathom root
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wait also

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the second part of the question asks "Is f(x) greater than or less than this function value when x is positive and large in magnitude?:"

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the answer is greater than but according to what you're saying, wouldnt the value of f(x) get smaller as x increases?

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because the denominator is increasing, making the fraction smaller?

cloud prism
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f(x) = 7 + a bit
so it is greater than 7 (the value just determined)

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it gets as close to it as you want to though.

fathom root
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wait so 7 would be the function value and the horizontal asymptote?

cloud prism
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yes

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well not the function value

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the function value would be f(x) which is always a little greater than 7

But I guess they refer to the asymptote as "this function value"

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Could be I'm completely mistaken :'D

Is there any more context?

fathom root
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uhh i dont think so

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this is all it provides

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as far as i can tell i dont see any other context

cloud prism
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Well seems like I was not mistaken after all

fathom root
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so are you saying like in a normal circumstance, the function value and f(x) are just the same thing?

cloud prism
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Well yes kinda, I'd expect that

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But that's language, and I'm not a native

fathom root
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ohh ok

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im native and i dont understand any of the language part

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probably more than you tbh xd

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ok as a final question, i jkust want to ask, when generally we say as x/f(x) approaches [some number], are we just describing when x/f(x) is just approaching an asymptote?

cloud prism
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not really. That works as a picture in this case as we go to infinity, but you can also approach specific values, like points where the function is not defined

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like 8 in your example f(8) = 7 + 1/0 which is not defined
but if we go very very close to f(8) from the right or left we can deduce some information about the function

fathom root
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oh ok

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alright thank you so much for the help

cloud prism
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but that is probably calculus stuff or comes later on

fathom root
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oh wait wait actually last question my bad

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so how could x go to infinity if the vertical asymptote is 8?

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or is that just an expression for x increasing

cloud prism
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your input value can be as large as you want

fathom root
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so is it just a discontinuity at 8?

cloud prism
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well we could figure that out by approaching f(8+e) and f(8-e) with e getting very small. If those match up there is literally just a hole there

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otherwise the function might jump at that point

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,wa f(x) = 7 + 1/(x-8)

fathom root
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ok gotcha

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alright thank you

cloud prism
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(and that's not a hole, that's a whole pole)

fleet yew
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Hole pole

thorn plank
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1st?

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@everyone

viscid thistle
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secondly, its barely comprehensible

willow bear
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what the actual fuck were you thinking trying to PING EVERYONE in a server of THOUSANDS, @thorn plank

thorn plank
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shut the fuck up

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bitch

viscid thistle
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<@&268886789983436800>

willow bear
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bruh

viscid thistle
#

my bad mods if this wasnt ping-worthy kindly forgive me for my terminal stupidity

quartz edge
#

derivatives are taught in high schools right? so early uni calculus wouldnt be the spot to post on for me rn

willow bear
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it depends

quartz edge
viscid thistle
#

no

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f(40) = 800

quartz edge
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what would f'(40) then be? 0

viscid thistle
#

yea

quartz edge
#

aah okay, thx

static thistle
#

logarithms are too exponents as inverse trigonometry functions are too __________

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what would this be

lime bolt
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Why do u care if he pings @everyone

wary stone
#

Oh nice it doesn’t work

viscid thistle
#

shut the fuck up
bitch
These were not acceptable

paper acorn
#

can someone assist me with this please

blazing parrot
#

okay for 1) try to write the trig functions they want (cos, tan, csc, cot) in terms of the ones u have the values for (sec, sin)

uncut mulch
#

drawing a triangle helps
then apply pythagorean identities and signs in quadrants of the unit circle

viscid thistle
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"At a point 150 fett from the base of a building, the angle of elevation to the bottom of a tower on top of the building is 32 degrees. The angle of elevation to the top of the tower is 50 degrees. Find the height of the tower alone."

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How do I do this?

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Like I am pretty lost with i

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it*

uncut mulch
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draw diagram

willow bear
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have you made a diagram? @viscid thistle

viscid thistle
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i made one rn but i only have it set as a right triangle, and i think the 150 would be the bottom part of it? like it is one of the sides that aren't the hypotenuse, and it isn't the height

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it's the length part of it for me if that makes sense

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so is the angle at the top 50 degrees? or is it the 30 degrees?

willow bear
#

try making a drawing of the actual setting

viscid thistle
willow bear
#

where's the tower?

viscid thistle
#

the one thing with the door lol

willow bear
#

no that's the building

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it has a tower on top of it

viscid thistle
#

oh there are two different stuff?

willow bear
#

think like a radio antenna or lightning rod

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it sticks out the top of the building

viscid thistle
#

ke this?

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like this?

willow bear
#

not quite

minor pivot
#

Can square root of 181 over 9 be rationalized ?

willow bear
#

$\frac{\sqrt{181}}{9}$ is already rationalized

obsidian monolithBOT
minor pivot
#

oh okay so there is nothing you can do with it?

willow bear
#

wym

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what are you trying to do with it

minor pivot
#

hypotenuse over opposite

willow bear
#

no, what are you trying to do with this number?

minor pivot
#

181 sq is hypotenuse and the opposite would be 9

willow bear
#

no, that is not what i'm asking you

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i am not asking you how you got it.

minor pivot
#

find the csc value

willow bear
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i am asking you, what are you trying to do now that you've got this number: sqrt(181)/9?

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what are you trying to do with the expression sqrt(181)/9

minor pivot
#

I'm wondering if that is my answer

willow bear
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i don't know, you haven't posted the problem

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so nobody can tell you whether or not sqrt(181)/9 is the answer to this mysterious problem, which it seems you expect people to magically know about

minor pivot
#

Use the Pythagorean Theorem to find the length of the missing side. Then find the trigonometric function of the given angle. Give an exact answer with a rational denominator. So I got a triangle the opposite side is 9 and the other side is 10. So I needed to find the hypotenuse which I did which is sq181

willow bear
#

you mean sqrt(181)

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okay, so like

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you're asked for csc(θ) where θ is the opposite angle to the side with length 10

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yes your answer is correct now

minor pivot
#

ya that's what I ment

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thanks sorry I didn't make things clear

viscid thistle
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oh i got the question lol

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it wasn't that complicated,

gritty stratus
hazy furnace
#

how get radius

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i used desmos to get answer is 73 but idk how

fervent abyss
#

it goes through 2, 5, so x = 2 and y = 5

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substitute and evaulate

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and then take the square root of the result

willow bear
#

@hazy furnace find the radius of your circle

fervent abyss
#

this is what they're trying to do, yes.

hazy furnace
#

idk how to do that

fervent abyss
#

I just explained it

uncut mulch
#

explaination was poor

fervent abyss
#

thanks, so am I

uncut mulch
#

apply the distance formula

hazy furnace
#

idk what that is

uncut mulch
#

look it up

hazy furnace
#

ok

fervent abyss
#

why are you making this more complicated than it needs to be

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plug in 5 for x and 2 for y, evaluate the expression and take the square root

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I'm not sure how that explanation is poor

hazy furnace
#

how i evalute experssion

uncut mulch
#

that works too I guess

fervent abyss
#

calculate (2-5)² + (5+3)²

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and then take the square root

hazy furnace
#

;calc (2-5)^2+(5+3)^2

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,calc (2-5)^2+(5+3)^2

obsidian monolithBOT
#

Result:

73
uncut mulch
#

dont even need to take the sqrt

hazy furnace
#

yeah

fervent abyss
#

oh nvm, no square root

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it was about the equation, not the radius

willow bear
#

i mean

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you can take the square root

uncut mulch
#

since you're not explicitly after the radius

willow bear
#

only to then square it immediately afterwards

fervent abyss
#

I didn't read the question properly, I just saw that they were asking for the radius

willow bear
hazy furnace
#

i dont understand how u get 2-5^2 + 5+3^2

willow bear
#

parentheses!!!

hazy furnace
#

idc

willow bear
hazy furnace
#

()()

fervent abyss
#

the circle goes through (2,5), so naturally, plugging those values in for x and y needs to result in an equation which equals the radius squared

hazy furnace
#

oh ok

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i see

fervent abyss
#

as the circle equation is the equation which all points on the circle have to satisfy

hazy furnace
#

,calc (1-4)^2+(5+3)^2

obsidian monolithBOT
#

Result:

73
hazy furnace
#

,calc (-3+1)^2+(2+3/2)^2

obsidian monolithBOT
#

Result:

16.25
viscid thistle
#

You can also use desmos :+1:

#

not sure which channel this belongs in, but what is the sum from k = 1 to n of k^4?

astral mantle
#

$\frac{1}{30}n(n+1)(2n+1)(3n^2+3n-1)$

obsidian monolithBOT
terse ravine
#

Oh I forgot the 36x^2+48x+16

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Then f'(2)=(10) / (36(2)^2+48(2)+16 = 5/128

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Never mind, was a mistake in typing out the correct ans. Sorry, for pinging :c

#

I've been doing Math for 8 hours already x.x

chrome thorn
#

What are the extreme points of x/(2-sqrt(x)) ? I found x=16 as maximum but in the book it's says there is one more point which is x=0

willow bear
#

,w d/dx x/(2-sqrt(x))

obsidian monolithBOT
willow bear
#

the domain is [0,4) ∪ (4, +∞)

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0 is a boundary point and a local minimum

chrome thorn
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But why? How can I find it algebraiclly

echo wagon
#

Extremum points occur where the derivative zero, or at the boundary points of the domain.

novel cargo
#

if a rational func has variables of even degree then it doesn't pass the horizontal line test and dosn't have an inverse

#

is this statement correct?

quaint mason
#

can someone explain how to do this problem?

polar heart
#

use the fact that $e\approx 2.7$

obsidian monolithBOT
halcyon granite
#

is there a way to find the extrema of a quartic instead of just plugging in numbers between roots

willow bear
#

take derivative and find zeros?

halcyon granite
#

without derivatives cuz i feel like my teacher wouldnt appreciate me using concepts we havent learned yet

willow bear
#

oh

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well then you're fucked ig

halcyon granite
#

yeah he kinda just told us to graph a quartic function and describe it, and he always wants to know the extrema and on the answer sheet he has the extrema, but doesn't show how he got to them

viscid thistle
#

$\pi$

obsidian monolithBOT
viscid thistle
#

$e=\pi=3$

obsidian monolithBOT
viscid thistle
#

Yes this is cursed

halcyon granite
#

very cursed

shadow plaza
viscid thistle
#

can someone help

#

i got homework its hard

quaint mason
#

@polar heart why is e approximately 2.7?

lime bolt
#

because it is

quaint mason
#

how so? @lime bolt

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like what makes u say that?

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I dont get how u get that answer

tawdry python
quaint mason
#

i get that but can u show the work?

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like how does that have anything to do w approximate values from a list of numbers

tawdry python
#

I cannot say that I can fully explain it to you, if you want a comprehensive answer check out Eddie Woo's video.

quaint mason
#

eddie woos?

tawdry python
#

it pops up in a lot of places and can usually be traced back to being related to exponential growth

quaint mason
#

he used a calculator, but the hw says not to, so is there a way not to use calculator or do u have to use calculator to solve for this

tawdry python
#

could I see the full question? I'm curious now

quaint mason
#

the one i posted above is the full explanation to the problem

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they give u a list of numbers, and find e-1

echo wagon
#

Oh, they clearly just expect you to know that e is approximately 2.7

tawdry python
#

Thats what my first thought was too

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I think that they're testing your knowledge of the approximate value of e

quaint mason
#

thats weird but ty yall

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whats with the list of numbers tho?

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like is it important in any way

tawdry python
#

I dont think so, it looks to be a set of options for you to choose from

echo wagon
#

Yes, they want to limit the correct answer to one. Otherwise someone who uses e = 2.7 and someone who uses e= 2.718 will enter different answers. Now you just have to choose the closest value in the list, so everyone has to choose the same one

tawdry python
#

It would be less confusing if they just asked
"What is the approximate value of [ e - 1 ], round to one decimal"

quaint mason
#

i see

night fiber
#

π=e=3

minor pivot
#

is the exact value of -7pi/4 =1 or -1?

#

tan

proud raven
#

so 2pi is a full rotation, yea?

#

and the negative means were starting at (1,0) and going anti clockwise

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so were almost going a full rotation anticlockwise

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youll land at a place where both the x and y coordinate are positive

#

so all you need to know is if the ratio of a positive number and a positive number is itself positive or negative @minor pivot

minor pivot
#

using a reference angle to find the exact value.

#

oh so it is 1 then

proud raven
#

yea

#

its 1 where the signs match

#

(of the x and y coordinates)

#

and -1 where they dont

minor pivot
#

oh so if the question was 7pi/4 it would be -1 right?

proud raven
#

yea 😄

minor pivot
#

thanks

ivory finch
#

It’s interesting looking at this channel. The US system is jarring for me- why do you wait till University to do some calculus aside from precalculus? The nature of the questions you get is also weird. Though perhaps it’s better- my country’s course infamously scars the mental health of most students and suicide isn’t uncommon.

#

Perhaps I should have said this in a different channel

dusty cape
#

anyone free here for a sec?

quaint mason
#

can someone explain why 10 is wrong

#

all i did was 4.67 divide by 4 because it is quarterly, then i got 1.1675. divide that by 100 turning it into decimal rather than percent and it becomes .011675. add 1 to that=1.011675. take that to power of 6 and multiply it all by 1000. where did i go wrong bruh?

#

to sum that all up

#

this.

willow bear
#

@quaint mason it's 6 months but 1.1675% is the quarterly interest rate, so you'll want to do this for 2 quarters, not 16.

quaint mason
#

wym i didnt do it for 16 quarters

willow bear
#

you say you raise it to the 6th power but then write 16 in the pic, which is a bit thonk

quaint mason
#

where u see 16

#

thats to the power of 6

willow bear
quaint mason
#

^

willow bear
#

you're already writing it as a superscript, why insert a caret

quaint mason
#

idk

willow bear
#

...

quaint mason
#

i just wanted to make it clear xD

#

sorry

#

but ye

#

i did that

#

and instead of 6

willow bear
#

anyway the exponent should be 2

quaint mason
#

i actually

willow bear
#

for 2 quarters

quaint mason
#

also did 2

#

and

#

thats wrong as well

willow bear
#

,calc 1000 * 1.011675^2

quaint mason
#

i caught the mistake

obsidian monolithBOT
#

Result:

1023.486305625
willow bear
#

1023.49 is wrong?

quaint mason
#

oh wait wow

#

my calculation is wrong

#

not that

#

ah i found out what i did wrong

#

for some reason my mind kept thinkin it stays 1.1675 even tho ik im suppose to do it the way i described...

#

sorry thats my calculation error

#

thank you :)

#

thats right, ty :)

copper breach
#

Can someone please check my work and help me understand how to do question b.) and c.)

#

asap please cause i'm trying to review for my upcoming test

#

ty

fiery wren
#

is this right?

proud raven
#

i think youre missing an angle?

#

@fiery wren

fiery wren
#

really?

#

i thought it was asking me to find the angle of the coterminal

#

isnt the coterminal of -pi/4 = 7pi/4

#

and the angle of 7pi/4 is 315?

quick mirage
#

Whatever fits 360n + theta should work

#

So 360(1) - 45 = 315 is one

fiery wren
#

and -315?

quick mirage
#

-315 is coterminal with 45 but not -45

#

And oops

fiery wren
#

yeah i understood dw lol

#

i'm either

#

overthinking or

#

doubting myself

#

so should i just leave it at 315 degrees

#

-315 degrees isn't coterminal with 7pi/4?

quick mirage
#

Nope because -315 is just coterminal with 360n - 315

#

360 - 315 = 45

fiery wren
#

gotcha

#

and while i have you here

#

in the midst of my breakdown and overthinking crisis

#

this is okay?

quick mirage
#

Actually there are two answers here

fiery wren
#

really?

#

i only found -45 degrees

austere void
#

+315 works too

quick mirage
#

When going clockwise, you go in the negative direction

austere void
#

ah equal

quick mirage
#

And that gives you -45

fiery wren
#

wouldnt it be -315 then

#

actually no, 315

quick mirage
#

When going counterclockwise, you get the equivalent positive angle

#

I wish i can draw a diagram here

#

But im on mobile

fiery wren
#

i drew it out a couple of times to make sure im not going crazy lol

austere void
#

(the mathematicians and clockmakers definitely had some kind of dispute in there)

fiery wren
#

i think im going clockwise

quick mirage
#

I woukd say negative and postive direction but thats a bit counterintuitive and confusing

fiery wren
#

lemme post my diagram

#

oops

#

lemme flip it

#

okay

#

it has to be 315

#

since it's going counterclockwise

quick mirage
fiery wren
#

thank you guys

quick mirage
#

No problemo

fiery wren
#

yikes

#

not correct

#

it was only -45 degrees apparently, not 315 degrees

#

which doesnt make sense to me

quick mirage
#

Well, when not considering the range 2 pi, but in general, it could be illogical to say that -pi/4 = 7pi/4

#

So its not entirely confusing

fiery wren
#

it's alright

#

thanks

quick mirage
#

But i guess they were looking for a specific answer

fiery wren
#

yeah

#

my math department's sadistic dude

quick mirage
#

Nah man, that was error on my part too. Humans, am i right?

#

Lol

fiery wren
#

it's all good brother

quick mirage
#

@fiery wren just wanted to correct something i stated before, coterninal angles can be found only on 360n+theta

fiery wren
#

noted

#

thank you

viscid thistle
#

for this I got

#

,tex $x \neq \ln({\frac{1}{2}})$

obsidian monolithBOT
viscid thistle
#

but apparently it's that

smoky pagoda
#

same thing

viscid thistle
#

oh

#

ok

smoky pagoda
#

by log rules

viscid thistle
#

Ohh yeaa

#

ok thank you

smoky pagoda
#

remember that $a\log{b} = \log{b^a}$

willow bear
#

and in particular log(1/x) = -log(x)

obsidian monolithBOT
viscid thistle
#

👍

narrow peak
#

hi

#

$\frac{20}{(x+3)(3x-1)}$

obsidian monolithBOT
narrow peak
#

is the partial frac decomp for tjis

#

this

#

$\frac{A}{x+3}+\frac{B}{3x-1}$

obsidian monolithBOT
smoky pagoda
#

Yeah, then solve for A and B

copper breach
#

Can someone please check my work and help me understand how to do question b.) and c.)

#

asap please cause i'm trying to review for my upcoming test

#

ty

#

I asked this question yesterday but again someone else asked a question right after ans no one replied to me wth

#

I would greatly appreciate if someone could help me

elder charm
#

what you did in a) is what you need to do for c)

cloud prism
#

But is a even correct

#

didnt you forget to apply the 3rd-root to the e-term?

elder charm
#

in a and b you just need to say that it's $64 e^{\frac{13\pi}{6} i}$ raised to the power $\frac{1}{3}$

obsidian monolithBOT
elder charm
#

didnt you forget to apply the 3rd-root to the e-term?
They did divide 13/6 by 3.

cloud prism
#

oh right, I totally missed that

copper breach
#

I did apply the third roof

#

Roof

#

Root

#

So I got 13pi/18

#

I don’t understand what powder the complex number is raised to

#

1/3?

#

Or do I saw the 13pi/18

elder charm
#

Yes, 1/3.

copper breach
#

Okay

#

Tysm

gilded brook
gilded brook
#

<@&286206848099549185>

gilded brook
#

Still need help for this one problem I really just don't know how it's done

#

First time seeing that symbol

echo wagon
#

Can you expand sin(x+φ) using the compound angle formula for sin?

#

Then compare what you get to what you have to rewrite

quaint mason
#

how do i solve for a and b?

#

does e just equal 2.7

elder charm
#

No, e here is the Euler's constant, the base of a natural logarithm, approximately 2.7182818284590452353602874713527 😛

#

how do i solve for a and b?
use the fact that $e^{n m} = (e^{n})^{m}$

obsidian monolithBOT
quaint mason
#

What

#

so

#

$(e^{-.007}^{t}$

obsidian monolithBOT
quaint mason
#

oops

#

$(e^{-.007}) ^{t}$

obsidian monolithBOT
elder charm
#

yes

quaint mason
#

wait then

#

2.7^-.007

#

would be percentage decay/growth?

vapid folio
#

my question is "solve the equation on the interval of 0 <= (theta) < 2pi."

#

the equation is cos(3theta) = 1

#

for some reason, the answer isnt 2pin/3

viscid thistle
#

Cuz theta is restricted to [0,2pi)

#

so n=0 is the solution

for some reason, the answer isnt 2pin/3

quaint mason
#

yes
@elder charm

#

I did what u told me to and

#

its wrong

#

apparently

elder charm
#

$14.825 e^{-0.007t} \approx 14.825*0.99302^t$

obsidian monolithBOT
quaint mason
#

wait

#

where did u get .99302 from

#

ah nvm

#

ty @elder charm

stoic fox
#

pls tell the product of these two - if it exists

#

and the inverces

cloud prism
#

Well you could start by calculating the first 3 entries of the product... You should see where you are going from there

willow bear
#

god fucking yikes

#

wait

#

aren't those the same matrix

trim cave
#

wait

#

you could add all the entries into one row

#

then take that out

#

then you'd be left with ones

#

then you'd subtract every row from one another until you get just one in the row with the ones

#

then you take the determinant of that

cloud prism
#

Why do I think, that he just came here to get the solution to his homework from somebody?

willow bear
#

@stoic fox

stoic fox
#

yes?

willow bear
#

these are both 10 by 10 matrices, do you think their product could be undefined?

stoic fox
#

thats exactly the reason why i said "if it exists"

willow bear
#

have you ever multiplied two matrices before

stoic fox
#

yes sir

echo wagon
#

The product of 10 by 10 matrices always exist, so you don't need that qualifier. So that's exactly the reason you don't need to say that.

#

What makes you think someone named Ann is a sir?

stoic fox
#

oh god

#

ok

#

yes sar

willow bear
#

"sar" thonk also yeah don't call me sir please

#

anyway multiplying two 10 by 10 matrices by hand is painful

stoic fox
#

ok fuck multiplication

#

can u do me the inverse

#

pls

#

sar

willow bear
#

what the hell is "sar" supposed to mean

#

anyway the inverse is even harder lol

echo wagon
#

And it might not exist

stoic fox
#

The villager way of saying "sir" since u guys didnt like it

viscid thistle
#

use wolfram alpha

stoic fox
#

no @viscid thistle stfu

willow bear
#

the issue isn't that we don't like the term "sir" it's that i'm not a man lol

stoic fox
#

what's ur age then

#

??

echo wagon
#

LOL

willow bear
#

how's that relevant

stoic fox
#

well i am 23

viscid thistle
#

why are you doing precalc at the age of 23

willow bear
#

i'm 21 but again how's that relevant to my not being a man

stoic fox
#

why are you doing precalc at the age of 23
@viscid thistle What can i do sar

echo wagon
#

why are you doing precalc at the age of 23
Why not? Don't be rude

stoic fox
#

Why not? Don't be rude
@echo wagon thanku sar

echo wagon
#

Please stop calling people sar and sir. It's p rude to keep doing it after you were called out. You don't know who is male here.

stoic fox
#

Ok my bad sorry sir / ma'am

#

oops

#

sorry again

#

mates

willow bear
#

if you insist on using "sir" or "ma'am" for me i'd rather you call me ma'am

stoic fox
#

Ok madume

echo wagon
#

And I am male, but I don't like sir. And I'm younger than you, so it's extra weird

willow bear
#

anyway

#

yeah, those are still ten by ten matrices

stoic fox
#

Ok madume undarstud

willow bear
#

...

stoic fox
#

...

willow bear
#

computing their product will literally take a thousand multiplications

stoic fox
#

Why u so lazy then

#

do it!

echo wagon
#

checks how long he has been on this server because this has to be a troll post

stoic fox
#

ok sorry

#

i will not ask anything then

echo wagon
#

Lol, you say you know how to multiply matrices, you're just too lazy to do it. So now you are asking us to do it. Ridiculous.

willow bear
#

Why u so lazy then
you expect me, a random stranger on the internet, to sit down and do literally 1000 multiplications BY HAND for you?

echo wagon
#

Use an online calculator

willow bear
#

and i'm the one who's lazy?

stoic fox
#

Guys, its frkn sarcasm

#

chillllllllll

#

Why u guys so serious

willow bear
#

how were we meant to know

echo wagon
#

So your whole post is a troll post?

willow bear
#

we aren't telepaths, we can't read your mind

delicate rivet
willow bear
#

halfway between high tide and low tide

#

whenever those are

delicate rivet
#

the function is y = 0.19cos(pi \7 x)+1.62

#

yea i used a calculator to find the derivative of function xbetween zero & 24

#

but on the answers, there are 2 sets of answers, one using only the max of the derivative graph and 1 using both the max and the minimum

#

which would be the correct one?

echo wagon
#

Do they give two different answers or two methods to get the same answer?

delicate rivet
#

yea, its the same method, 2 sets of answers

#

but one teacher uses both the min & max and one only uses the max

echo wagon
#

Show us?

delicate rivet
willow bear
stoic fox
#

Thank you !! @willow bear

#

I did it btw

#

i can verify now

#

thank uuu

echo wagon
#

Pink is correct @delicate rivet

delicate rivet
#

okieee tysmm,

echo wagon
#

The sign of the derivative only indicates whether the tide is increasing or decreasing, not the speed at which it is doing it.

delicate rivet
#

wait can u explain why?

#

ohh ty!

echo wagon
#

So you want the biggest magnitude of the derivative, without caring about the sign. So when it is + or -

delicate rivet
#

thank you again!

echo wagon
#

Np

obsidian monolithBOT
delicate rivet
#

nvm i figured it out

fast pawn
#

math sucks anyways

velvet blade
#

math sucks anyways
@WaidenWolf#6153 what is cool in your opinion?

shadow plaza
#

They left. Lol

opal rain
#

what should you first do here?

uncut mulch
#

product rule

worthy summit
#

Hi guys, I need help with difference quotients and rational expressions

#

More specifically I'm struggling with finding the difference quotient of rational expressions with square roots

viscid thistle
#

do you have an specific problem that you are stuck with?

worthy summit
#

Yes, f(x)= -sqrt of 8x-35

#

I know that f(x+h) is -sqrt of 8(x+h)-35

#

and I know how to set the equation up, but I get lost with the correct terms that need to be figured out

uncut mulch
#

what do you have atm

worthy summit
#

(-sqrt8x+8h -35 - -sqrt8x-35)/h

uncut mulch
worthy summit
#

Sorry but that doesn't help me

#

I don't know what to do after that step

uncut mulch
#

just to be clear:
$$f(x) = -\sqrt{8x} -35$$
right?

obsidian monolithBOT
uncut mulch
#

$\frac{f(x+h) - f(x)}{h} = \frac{ -\sqrt{8(x+h)} - 35 - ( -\sqrt{8x} -35)}{h}$

obsidian monolithBOT
sick seal
#

howdy yall, here on question b im struggling to find out how to implement the perimeter as an expression in terms of l.

#

bc i feel i somehow have to add (length2)+(width2)=335 somewhere in here

#

but g is asking for area...

fading token
#

area = length x width

sick seal
#

well yeah, but how do i show that when (length2)+(width2)=335

fading token
#

Note that you're essentially asking the question: "how do I separate $w$ when I have the equation $2l+2w=335$?"

obsidian monolithBOT
fading token
#

Does it help you when it's framed like this?

sick seal
#

to a degree, im just not sure how w fully disappears since it cannot be in the final expression.

fading token
#

Are you aware that $w= (335 - 2l)/2$?

obsidian monolithBOT
sick seal
#

yes

#

wait

#

oh fuck im dumb

fading token
#

Glad you realized before I spelled it out

worthy summit
#

ramonov:
@obsidian monolith place the -35 under the radicand and then simplify it further

#

@uncut mulch

pallid geode
#

Can anyone help w this

viscid thistle
#

Vieta

#

Use that

pallid geode
#

Whats b?

#

@viscid thistle

viscid thistle
#

-28

pallid geode
#

How would I go about this since i just got x=54 and other two x=0

viscid thistle
#

What?

pallid geode
#

Oh my bad i read it wrong

#

Technical mistake

viscid thistle
#

oh okay

pallid geode
#

@heady linden is asking about this

viscid thistle
#

Ok

#

So

#

You know whats a double root

heady linden
#

yes

#

i tried vietas already cause it is a similar problem but they didnt really work

viscid thistle
#

What did you do

heady linden
#

hold up

#

one sec

celest void
#

8 = pq^2
-8 = 2pq + q^2

#

where p, q are roots of cubic

heady linden
#

8?

celest void
#

Lead coeff 2

#

2(x-p)(x-q)^2 = 0

heady linden
celest void
#

Nono you are correct

#

p = -1/2, q = 2

heady linden
#

oh wait how did you get that

#

like i guess i did something wrong in my calc

celest void
#

m = -2(-1/2 + 4) = -7

#

-2 = pq^2, 2 = 2pq + q^2

#

pq = -2/q sub into second equation get a pretty easy cubic

#

pretty hard precalc prob tbh

viscid thistle
#

Hard ?

heady linden
#

i am

pallid geode
#

Same

celest void
#

I do not expect school to give this type of prob

pallid geode
#

Its not school its extra curricular

celest void
viscid thistle
#

it's fine

#

Here

#

Competition is not for this tiny stuff

celest void
#

welp

heady linden
#

my mistake was that i used an-1 subscripts from the wrong sides so i was using the wrong coeffs

#

so close yet so far :((

#

smh

unkempt burrow
#

The n is negative should I inverse all signs?

steel venture
#

yes

unkempt burrow
#

yes
@steel venture so -(bp/k)+4?

steel venture
#

yes

unkempt burrow
#

thank you

latent fern
#

Could I have help for my practice test?

#

So then I could ace the math test I have tomorrow

uncut mulch
#

did you already attempt it?

latent fern
#

I have attempted partial of it but parts I am stuck on

uncut mulch
#

go through the whole thing, preferably in a test environment first

#

and we can guide you on what you missed / need to work on

latent fern
#

okay

#

want me to list off a problem?

uncut mulch
#

sure

latent fern
uncut mulch
#

not really pre-calc

latent fern
#

....

quick mirage
#

When you want to isolate for a term like b, all you need to do is do the backwards operations of PEDMAS

#

or BEDMAS

#

or whatever it is in your educational system

latent fern
#

Yes PEMDAS

uncut mulch
#

but where did you get stuck?

latent fern
#

On the adding... of -2 lol

uncut mulch
#

consider adding 2 to both sides

latent fern
#

Okay I did that but after that is what I got stuck on

uncut mulch
#

$\frac b4 - 2 \red{+ 2 } = -1 \red{+2}$

obsidian monolithBOT
uncut mulch
#

what do you have after that

latent fern
#

That’s what I got stuck on

#

I knew to do that but not so much after the fact

quick mirage
#

Think of it this way
$+2-1$

obsidian monolithBOT
latent fern
#

Okay yeah

#

But I got stuck on the fraction

quick mirage
#

You're left with $b/4 = 1$

obsidian monolithBOT
latent fern
#

B=4?

uncut mulch
#

lowercase b

latent fern
#

Well yeah... sorry I’m dumb

uncut mulch
#

to get from b/4 to b, you could multiply by 4,
so you could multiply both sides of the equation by that

latent fern
#

THANKS

#

Okay thats actually sooo helpful

#

I know im not too bright..

#

I think I know how to Ace this test tomorrow thanks!

slow geode
#

hey so uh

#

how would i go about finding the inverse of 2e^x-e^-x

obsidian monolithBOT
willow bear
#

x = 2e^y - e^{-y}, solve for y

somber yew
#

I saw a proof for the associativity of function composition, can someone explain the reasoning behind the steps marked with (?)

willow bear
#

half of these lines dont make sense notationally

#

you meant (f o (g o h))(x)

somber yew
#

This is how Tao wrote them catThink

willow bear
#

are you sure you didnt make any typos

somber yew
#

Let me recheck now

#

Nope, none. This is verbatim from the book.

willow bear
#

weird

somber yew
#

Should I quote the definitions too?

willow bear
#

no errata?

#

do you have a pdf

somber yew
#

Uh lemme check on Tao's blog

#

No, a physical copy.

willow bear
#

brhu

somber yew
#

Nope, none of these lines is mentioned in the errata(although another line from the same proof is).

#

Aight one screw up on my end 😅

#

Sowwy

willow bear
#

this is basically symbol-pushing but basically

#

f(g(y)) = (f o g)(y) where y = h(x)

somber yew
#

This just looks like we assume what we want to prove

#

How does the third step move to the fourth?

#

f(g(y)) = (f o g)(y) where y = h(x)
Hmmmm this makes more sense.

#

But I'm not yet entirely convinced about how this argument is working, I know it should be true but this symbol pushing feels weird.

#

Is there an alternate way to prove it? Perhaps by using some arbitrary elements?

willow bear
#

it should be obvious that applying (h, then g), then f and applying h, then (g, then f) should give the same result tbh

somber yew
#

Oh, okay. Thanks!

unkempt magnet
#

does this just mean that if 0 < |x-5| < delta = epsilon then 0 < epsilon because |f(x)-7| = |7-7| = 0 so |f(x) - 7| < epsilon ???

shell isle
#

Does anyone know how to do the integral of cos^6 x sin^3 x dx ?

blissful ridge
#

Have you tried something?

worn anvil
#

I can't figure this out, anyone got a clue

viscid thistle
#

consider trying to identify the parent function by it's looking and then apply their function transformations

shell isle
#

I got it, I messed up on a trig identity

misty ocean
subtle mist
#

@misty ocean arccos(-sqrt(3)/2) = 5 pi/6 =/= 7pi/6 hence the first statement is true and the second is false. This is from the fact that cos(x) is not injective as several inputs corresponds to the same output, i.e cos(7pi/6) and cos(5pi/6) is both equal to -sqrt(3)/2

#

being injective means that for all x y in some domain is a set S, then f(x) = f(y) => x = y

sick seal
patent beacon
#

Then t = √[x/21]
And you don't need to worry about the negative sqrt

sick seal
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ah

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thanks mate

sick seal
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bc if F(x) is the cropped with and x is the original width...

lime bolt
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it is just x-3

sick seal
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this is stupid. why tf is that question here.

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confusing me by taking me back to 3rd grade

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istg

fiery wren
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is it a and b?

uncut mulch
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no

fiery wren
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i think it's just b

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it threw me off when it's asking to select all that applies

uncut mulch
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have you tried drawing b?
does it help you get what you want?

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the question is also poorly worded

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my interpretation of b is that only 2 sides are known to be 1, the third is unknown

lusty falcon
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Im a little confused on this could I get some help?

gritty meteor
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hello men

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i need help

terse ravine
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I got lost at 6/(x+6)^2 = 5

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Then I ended up at x+6 = (+-sqrt30)/5