#help-28

1 messages · Page 273 of 1

stone meteor
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lol

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2 or more

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in each

rare dock
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that’s the only one

stone meteor
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okay

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n = 3 so {0,1,2,3}

sterile torrent
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There is no pattern

stone meteor
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I think there is

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are you sure that table is correct

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or is that gpt

sterile torrent
stone meteor
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and they got that?

sterile torrent
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They did that for every n between 1 and 9

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And it's all correct

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We even checked manually until n=6

stone meteor
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the n = 3

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answers

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for {0,1,2,3}

sterile torrent
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Ofc
but it's in french

stone meteor
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this is not making sense

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did you mean A+B = (0,1,2,4,8,...,2^n)

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your definition asks for pairs of sets that would add up to {0,1,2,3} for n =3

sterile torrent
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no
i just rephrased the question to make the context more clear

stone meteor
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bro what

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can u just list

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the 4 pairs

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for {0,1,2,3}

sterile torrent
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In case you want to check the original question its problem 4

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A B
0 1 2 0 1
0 1 0 1 2
0 2 0 1
0 1 0 2

stone meteor
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so order matters?

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I'm confused on the question

sterile torrent
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Yes

stone meteor
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and I have no idea how it corresponds to what you asked

sterile torrent
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multiplying 2^m x 2^n is like adding m and n

stone meteor
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maybe if you could translate the question in english I could help

fierce cedar
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I landedddd

stone meteor
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{0,1,2,3,4}

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{0,1,2,3}, {0,1}

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{0,1}, {0,1,2,3}

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{0, 1, 2}, {0, 1, 2}

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{0,1,3}, {0,1}

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{0,1}, {0,1,3}

full forumBOT
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@sterile torrent Has your question been resolved?

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cold sail
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been trying 2b for ages now

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cold sail
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im just lost

rustic frigate
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What have u tried

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@cold sail Has your question been resolved?

cold sail
rustic frigate
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It’s a bit obvious once you see it

cold sail
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i think i realilsed something tho

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ye i wanna tyr solving it myself

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i just realoised that R is a subset of R- tho lol

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im gonna try showing E\M is in R- then prolly

cold sail
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🙏

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wait

cold sail
cold sail
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so far (E\M) U (N\M) and i know N\M is null

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i dont think this route goes anywhere tho

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cz i cant show E\M is in R ( i think)

rustic frigate
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Might be helpful

cold sail
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maybe i should sleep on it idk cz ive been trying since like before 2am

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my brain is tired

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lol

cold sail
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Yea I’m cooked

rustic frigate
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No

cold sail
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Do u think I should just try tmrow lowkey I wanna solve it tho

zenith kernel
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(E cup N)-M = (E-(E cap M)) cup (N-(N cap M)). Clearly N-(N cap M) is null so you are trying to prove E-(E cap M) is in R?

rustic frigate
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E\M must not lie in R

rustic frigate
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Good night rest is important

cold sail
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I been working for 12 hours

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😭

zenith kernel
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Equivalent to E cap M being in R

cold sail
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But I kinda have to I wanna ace these exams

zenith kernel
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How though… E cap M in R… this null set definition, can it somehow make us write E cap M is countable union or intersection?

cold sail
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What is cap

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Is it that \

rustic frigate
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Intersection

rustic frigate
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Does not have to be true

zenith kernel
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E-E cap M is in R iff its complement , which is E^c cup (E cap M) is in R

cold sail
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This is the first time I struggled so much on a module

zenith kernel
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E^c is in R so we need E cap M is in R right?

rustic frigate
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Take e.g. Lebesgue measure on [0,1]

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Then pick your favourite non measurable null set

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Let E = [0,1]

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Notice that E\M is non measurable

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And so is E cap M

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So it does not at all need to be in R

zenith kernel
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I can’t think of a null set this case. You have any?

rustic frigate
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It’s non constructive

cold sail
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What does lebesgue measure on [0, 1] mean

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Ik a levesgue measurable set

rustic frigate
cold sail
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Yes

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Not always tho right

rustic frigate
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For lebesgue measure that’s the definition

cold sail
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Oh y we were given a defn with symmetric differences

zenith kernel
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Lebesgue case it’s done by defining outer measure μ first then measurable sets are A satisfying μ(X cap A)+μ(X-A)=μ(X) for any out measurable X

cold sail
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Ye

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That’s the one I know

zenith kernel
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But yours is a general one not having outer measure things…

cold sail
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Ye

rustic frigate
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That’s a condition for a set to be measureable given any outer measure…

cold sail
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Ok so E\M

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What do I do with this

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I was thinking of stuff like sunsets but

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*subsets

rustic frigate
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All im saying so far is that you can’t show this is in R

cold sail
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But I’m not sure how taking a subset will help me

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Ye I get that

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Doesn’t follow from sigma algebra axioms

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Ok so

zenith kernel
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I was suggesting trying to show that E cap M, which is null and a subset of a member of R, is in R. Aslan thinks it’s wrong but I haven’t come up with a counterexample following his idea.

cold sail
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I know M is a null set which means there exists F in R with 0 measure and M is a subset of F

zenith kernel
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That’s the thing. I can’t come up with a null set.

cold sail
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And that (E\F) is a subset of (E\M)

zenith kernel
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A set contained in any measure 0 set, doesn’t exist right? Only empty

rustic frigate
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I said pick M to be any non measurable null set

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This can only be done non-constructively

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Using e.g. axiom of choice

cold sail
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Am I going in the wrong direction

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Or na

zenith kernel
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This null set definition, X is a null set iff X is contained in any measure zero set, like {r}. So X is empty in Lebesgue case

rustic frigate
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Nope

zenith kernel
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Shit, for some, I thought for any

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My bad

rustic frigate
cold sail
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Fine I’ll go sleep lol

rustic frigate
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But that doesn’t seem bad

zenith kernel
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What’s your idea again? I also want to figure it out.

rustic frigate
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I can give it away but I don’t think you’ll find it satisfying

cold sail
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True

rustic frigate
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It’s obvious once you see it

cold sail
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I’m currently straddling this lane of

zenith kernel
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A sketch maybe?

rustic frigate
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And is not really illuminating

cold sail
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I wanna solve t but I also can’t afford to waste too much time as I have other modules to revise for

rustic frigate
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Sleep is also very important

cold sail
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True

rustic frigate
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Should be top priority

cold sail
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  • acing exams 🥶
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My notes teaches measure theory so terribly

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I only know lebesgue measure through the outer measure definition

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It’s also cz this isn’t even a measure theory course it’s a functional analysis course with some measure theory in it

rustic frigate
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I’m doing functional analysis rn too

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But I had measure theory before this course

cold sail
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50x better than me 😭

rustic frigate
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No?

cold sail
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My functional analysis course is kinda light too

rustic frigate
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You’re doing well

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By getting a well night sleep you’ll feel and perform alot better

cold sail
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Prob I don’t think I’ll still be able to solve it tho

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But I’ll try

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I need to catch up on complex analysis I’m so behind on that as well

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Luckily for me complex analysis is kinda trivial

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Compared to functional analysis anyways

rustic frigate
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Yes I’m struggling with functional analysis

cold sail
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It’s just like

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How do u just think of a Cauchy sequence of functions that does not converge in the sup norm

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😭

rustic frigate
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Once we started with Hahn-Banach and duals, weak-topologies I started getting overwhelmed

zenith kernel
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How about I find a null set M’ containing E cap M, such that E-M’ is measurable?

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By definition we have this M’, just that F in the definition “for some F”, right?

rustic frigate
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Hm?

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But we want them to be the same element

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Just rewritten as a union

zenith kernel
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This is the union:
E- (E cap F)
union
(E cap F) - (E cap M)
union
N-E-M
Measurable null null

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null cup null is still null by a)

rustic frigate
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Anyways good night!

zenith kernel
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Thanks. Didn’t think of that F.

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@cold sail Has your question been resolved?

solemn fable
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Hello?

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drifting summit
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drifting summit
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can someone fully work out the algebra for this 😭

zenith kernel
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Which part you don’t understand?

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It seems very clear, on one hand the residue equals the coefficient a_ -1 of the Laurent series, on the other hand by Residue theorem it equals the integral in the bottom

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.

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@drifting summit Has your question been resolved?

zenith kernel
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Or your issue is not understanding why we come up the other integral?
We let w=1/z, f(w)dw=f(1/z)d(1/z)=-(1/z^2)f(1/z)dz so the original integral over C clockwise become (1/z^2)f(1/z) integral over C’=circle of radius 1/3 anti clockwise. That’s why we got that new integral

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C’ is of radius 1/3 and it has only one singular point 0 inside it

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drifting summit
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@zenith kernel getting 1/z^2f(1/z) = 1/z(-3/2 + a1z + ...)

drifting summit
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is it jus

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ugh

zenith kernel
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Go on, what is the issue

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(5 singularities in C, that’s why we change into integral on C’ where only one singularity 0 is inside C’ by the way, by w=1/z substitute)

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If you prefer I can calculate directly for you without this substitute, and obtain the same result

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@drifting summit Has your question been resolved?

zenith kernel
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Anyway it will be calculating the sum of value of f(z)(z-a) plugging in z=a, like -4/3+Σ_i (s_i ^3-3/2)/(s_i+1)Π(s_i-s_j) for j !=i, where s_1,…,s_4 are four roots of z^4+1/2=0, then multiply by 2πi. i am sure it will be the same result, but ton of calculations involved

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$\frac{4}{3}+\sum_{i=1}^{4}\frac{s_{i}^{3}-\frac{3}{2}}{(1+s_{i})\prod_{j \neq i}(s_{i}-s_{j})}$

glossy valveBOT
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Cogwheels of the mind

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dawn owl
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how did they find A^(-1) ? i mean ik how to find it by RREF with identity matrix, but is there a shortcut of doing so?

zenith kernel
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You know A^-1=(1/det(A))(the adjoint matrix of A)?

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2 by 2 case, A=(a,b;c,d). The adjoint of A is simply (d,-b; -c,a)

dawn owl
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smth like that

zenith kernel
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Then you need to know adjoint matrix. Laplace expansion in the case of one row/one column gives you A(adjoint of A)=det(A)I

dawn owl
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but i mean i could have done this the long way ig

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but youre right anyways, i should learn that

zenith kernel
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If you just want to solve your problem, compute directly that (a,b;c,d)(d,-b;-c,a)=(ad-bc,0;0,ad-bc)

dawn owl
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ok , thxx !! 🙂

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low violet
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help

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low violet
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heres my question:

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Mass if Box A: Mass of box B = 4:7
The mass of box B is 2.4kg more than the mass of box A. Calculate the mass of box A and the mass of box B.

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and

chrome dew
low violet
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Q9: a group of 12 adults and 9 children travel on a bus. The cost of an adult ticket is n$. The cost of the child ticket is $(n-10). The total cost of the ticket is $277.50. Find the cost of one adult ticket.

chrome dew
low violet
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how?

chrome dew
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Which one do you want to start with

low violet
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do i do this?

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:

onyx glen
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!1q

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low violet
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4/11 x b+2.4

fallen salmon
low violet
chrome dew
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Not quite 4/11

low violet
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?

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7/11

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mb

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right?

chrome dew
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Think about it like this: if Box A is 4kg then Box B must be 7kg right

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So whatever equation you come up with that relates the two, plugging in these numbers should work

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You can also rewrite the ratios as fractions if that helps

low violet
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ok

chrome dew
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Did you manage to get the equations yet?

low violet
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i asked copilot

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i dont get his working

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why did he do 7'x'

chrome dew
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You know how the ratio is 4:7

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Like 4 parts to 7 parts

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Here x represents the value of one 'part'

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This is another way to do the question but not the one I was describing earlier

low violet
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11 is total ratio

low violet
chrome dew
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You want me to ask copilot to do it??

low violet
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?

chrome dew
low violet
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me*

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mb

chrome dew
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Oh ok ok

low violet
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i have an exam tmrw

chrome dew
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Let's say m_a and m_b represent the mass of box A and B respectively

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If we rewrite the ratio as a fraction then we get m_a/m_b = 4/7

low violet
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than what?

chrome dew
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Then the second piece of information can be written as m_b = 2.4+m_a

low violet
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ok

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than?

chrome dew
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Then you solve the simultaneous equations

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Are you familiar with how to do that?

low violet
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execution method?

chrome dew
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Did you mean elimination?

low violet
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yes

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same meaning

chrome dew
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Yeah you could do that but I think substitution method is easier here

low violet
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could u make the simultanious any easier fo rme to learn cuz that is so f'd up for me

chrome dew
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wdym

low violet
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ok nvm'

chrome dew
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Ok let's try break it down

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If the cost of an adult ticket is $n then how much does it cost for 12 adults?

low violet
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12n

chrome dew
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Yes good

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If the cost of a child ticket is $(n-10) then how much does it cost for 9 children?

low violet
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9(n-10)

chrome dew
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Good good

low violet
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wat...

chrome dew
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So then what's the total cost in terms of n

low violet
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ok ok

low violet
chrome dew
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Yes exactly

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But you also know the total cost is 277.50

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So...

low violet
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nvm i got it solved

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u can close this

chrome dew
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Ok gl for your exam!

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Maybe you have to close it?

low violet
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idk how

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u guys have command

chrome dew
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Type ".close"

low violet
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.close

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low violet
#

no u guys have to do it

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low violet
#

.close

dawn owl
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dawn owl
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any hint for solving it will be cool

brittle sun
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Well you could just substitute the two vectors into AX = b

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And then sub the third and use information from the first two subs

dawn owl
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subtitue only gives A*(5,0,1)=b for example

fast peak
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can you find a solution to Ax=0 ?

dawn owl
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and perhaps m>3

fast peak
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you have two solutions Ax=b and Ay=b

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what can you do with those

dawn owl
fast peak
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yes

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continue

zenith kernel
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{x: Ax=b} is a linear space of {x: Ax=0} plus some vector. So Ax_1=b=Ax_2, you can make x_3-x_1 and x_2-x_1 in that same null space. And this null space you already know a one dimensional subspace of it so…

dawn owl
fast peak
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yes they are but I deliberately did not use those words

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Ax=Ay

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so A(x-y)=0

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what can you say about A(x+lambda(x-y)) ?

zenith kernel
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x_3-x_1 is in that space, the natural way is to let it in F(x_2-x_1) I meant. But anyway I don’t know how to phrase it without mentioning linear space

dawn owl
fast peak
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its just a variable

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just a number

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what can you tell me about A(x+17(x-y)) ?

dawn owl
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if thats the direction of what youre sayin

fast peak
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I just want you to multiply it out

dawn owl
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i aint sure

dawn owl
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but im trying to understand your stance

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ive found how to get the answer , thx

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torn jolt
#

What in the wee man?! HELP PLS😰

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torn jolt
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I made a mistake and those sin and cos is messing w/ me

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Math be preaching to me😟🫣

burnt grotto
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yikes

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trigonometry is my weak point too

torn jolt
burnt grotto
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Fr

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your first step seems totally fine,

torn jolt
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on the line of 2tan/1-cos^2delta is where I messed up after

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Cause idk what to do next and I assumed a bunch of stuff then it made it look all funky

burnt grotto
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check line 5

torn jolt
sudden chasm
foggy vapor
glossy valveBOT
burnt grotto
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nvm I thought there was smth wrong

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there isn’t

torn jolt
burnt grotto
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lien 6

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sinx actually cancels here

ancient zinc
burnt grotto
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oh oh that’s also an error

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there are two errors in this solution

torn jolt
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Am I on the right track now?

burnt grotto
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why’d you undo the thing

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you get 2/sinxcosx

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that’s exactly what they ask for

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one of the sinx cancels

torn jolt
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😅I confused

burnt grotto
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from 2sinx/cosx whole divided by sin^2x

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the sinx in the numerator and denominator cancels

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and the cosx goes into the denominator

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so you get 2/sinxcosx

torn jolt
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No

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It’s squared

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Cannot be cancelled

burnt grotto
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sinx times sinx

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you split it into that and cancel it

torn jolt
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No burp I need to equate the denominator to have a sin at the bottom

burnt grotto
torn jolt
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No it’s squared

burnt grotto
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sin^2x = sinx times sinx?

queen flame
torn jolt
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😵‍💫

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Can you explain from 2tan delta/sin squared delta

burnt grotto
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ok

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so we have $\frac{2tan(x)}{sin^2(x)}$

glossy valveBOT
burnt grotto
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$tan(x)=\frac{sin(x)}{cos(x)}$ ok?

glossy valveBOT
burnt grotto
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you with me?

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we can substitute this into our first equation

torn jolt
burnt grotto
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$2\frac{\frac{sin(x)}{cos(x)}}{sin^2(x)}$

torn jolt
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Is sin over cos equals to 1? But my teacher didn’t teach us that for AS

glossy valveBOT
slate violet
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and that's in AS

torn jolt
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Yes that’s what I thought

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I did get that

torn jolt
burnt grotto
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so now we split $sin^2(x) = sin(x)\cdot sin(x)$

burnt grotto
torn jolt
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Ok…

glossy valveBOT
burnt grotto
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and this main equation becomes

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$\frac{2sin(x)}{sin(x) \cdot sin(x) \cdot cos(x)}$

glossy valveBOT
burnt grotto
#

the answer is right in front of you now

torn jolt
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Sin x means cos times tan?

burnt grotto
#

yeah but that identity doesn’t help herr

burnt grotto
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if you did then congratulations, you are one step away from the answer

torn jolt
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Okkkk gracias 🙏🙏

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austere cove
#

From Dummit and Foote:

Let $N \trianglelefteq G$. If $\overline{H} \leq G / N$ is a subgroup of $G / N$, the complete preimage of $\overline{H}$ in $G$ is the preimage of $\overline{H}$ under the natural projection homomorpishm.

As an exercise, to understand the definition, I attempted to construct a very simple example.

Let $G$ be $Z_8$, and let $N$ be $Z_2$, then $G/N = {{0, 1}, {2, 3}, {4, 5}, {6, 7}} \cong Z_4$. If we have $\overline{H} = Z_2 \leq Z_4$ then $H = {{0,1}, {4,5}}$ so its preimage in $G$ would be ${0,1,4,5}$.

Is this accurate? This would seem to imply that $\overline{H}$ is not a subgroup in $G$. Is this expected? What is the complete preimage used for? (Why is it complete?) All of the references to this concept online seem connected to Dummit and Foote, is this concept known by a different name in other texts?

glossy valveBOT
#

OmnipotentEntity

brittle sun
#

The way you've written G/N feels wrong

#

Like I get what you're trying to say but why is G/N = 0,1,.., 7

fast peak
#

that part is just latex error

#

look at the original tex

brittle sun
#

Oh lmao

fast peak
#

but something is wrong with those cosets

brittle sun
#

There is

fast peak
#

so N={0,2,4,6} ?

brittle sun
#

You can't just take Z_2

fast peak
#

or what do we mean by Z_2

brittle sun
#

You have to take a subset of G that's isomorphic to Z_2

fast peak
#

or do you want N={0,4} ?

brittle sun
#

Which would be {0,4}

#

So the cosets would be 0,4;1,5;2,6;3,7

fast peak
#

in the first case you would have G/N = {{0,2,4,6}, {1,3,5,7}}

#

in the other you would have G/N = {{0,4}, {1,5},...}

austere cove
#

oh my bad

brittle sun
#

You don't mod just by groups

#

You mod by subgroups isomorphic to those groups

austere cove
#

right

#

So I would have $G/N = { {0,4 }, {1, 5}, {2, 6}, {3, 7 } }$, thus $\overline{H} = { {0,4 }, {2, 6} }$, which is a subgroup of $G$, so that's cleared up.

glossy valveBOT
#

OmnipotentEntity

austere cove
#

well, it's a subgroup of G when unboxed.

ancient solar
#

btw, it's nice to know that the preimage of a subgroup under a homomorphism is always a subgroup

austere cove
#

That's something I figured that should be true, which is why I was confused.

brittle sun
austere cove
#

so, what's the motivation behind defining a "complete" preimage, and why is it considered complete? And does it have any other name? I grepped my entire digital textbook collection, and thumbed through about half a dozen abstract algebra books that I own, and I can't find another reference to it.

uncut cedar
austere cove
#

it's a subset of the domain of a function.

brittle sun
uncut cedar
#

oh I see

brittle sun
#

The fact that it's in DnF feels weird as fuck

austere cove
#

lol

brittle sun
#

Complete seems to mean maximal in this context

#

"This is the set of elements that would map to H under the quotient"

#

Which, sure, but I don't see why we need a separate name for this cuz it doesn't seem like it'll ever show up again

ancient solar
#

yeah, I have also never heard of this term, I feel like there's no need to have a dedicated term for this

austere cove
#

ok, so the concept is uncommon enough that it only has one name that one author gave it, and it never really caught on because it isn't generally useful.

#

Thanks so much! 😄

#

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red rampart
#

Can someone give me some concrete directions on how to determine whether this expression is always greater than or equal to 0 for π/4<x<π/2? I’ve tried substituting t=tan(x/2) and also using derivatives, but I still can’t find a solution to this problem

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lucid cairn
#

hello why is this wrong

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lucid cairn
#

i looked at this

robust slate
#

$(a^b)^c=a^{bc}$, not $(a^b)^{ac}$

glossy valveBOT
#

Civil Service Pigeon

robust slate
#

idk what happened at the end tbh

lucid cairn
#

so 2 to the power of 2+6=8

robust slate
lucid cairn
blissful sail
delicate torrent
glossy valveBOT
#

1 divided by 0 equals Infinity

blissful sail
#

Just multiply the outer most power with the one inside

lucid cairn
delicate torrent
glossy valveBOT
#

1 divided by 0 equals Infinity

delicate torrent
#

@lucid cairn

bitter star
glossy valveBOT
#

Yash_AR

delicate torrent
glossy valveBOT
#

1 divided by 0 equals Infinity

lucid cairn
#

why dont i power the 2 aswell

bitter star
lucid cairn
#

in here they power the 2 aswell

#

@delicate torrent

blissful sail
lucid cairn
#

wdm

blissful sail
#

In the problem you originally posted, there was (2^3)^2

delicate torrent
glossy valveBOT
#

1 divided by 0 equals Infinity

blissful sail
#

Yeah this

delicate torrent
glossy valveBOT
#

1 divided by 0 equals Infinity

delicate torrent
#

These are 2 different things

delicate torrent
glossy valveBOT
#

1 divided by 0 equals Infinity

delicate torrent
glossy valveBOT
#

1 divided by 0 equals Infinity

blissful sail
# lucid cairn yh

But in the second case there were two terms multiplied (2 and x^2) and the whole thing was raised to the power 3, so the power gets distributed to the multiplied terms

lucid cairn
#

ok

#

so whats the rule here

#

if its 2 stuff inside the bracket then u power both

#

but 1 stuff inside the brackter you power it once?

#

like this?

delicate torrent
#

Hear me out bro

lucid cairn
#

yh

delicate torrent
#

So imagine this

#

$a^b$ is just $a$ multiplied $b$ times

glossy valveBOT
#

1 divided by 0 equals Infinity

lucid cairn
#

yes

#

ok

delicate torrent
#

And according to the definition, what's $(a^b)^c$?

glossy valveBOT
#

1 divided by 0 equals Infinity

lucid cairn
#

a to the power bc

delicate torrent
#

It's just $a^b$ multiplied $c$ times

glossy valveBOT
#

1 divided by 0 equals Infinity

lucid cairn
#

yh

delicate torrent
#

And because $a^b$ is just $a$ multiplied $b$ times

glossy valveBOT
#

1 divided by 0 equals Infinity

delicate torrent
#

How many $a$s are multipled together in $(a^b)^c$?

glossy valveBOT
#

1 divided by 0 equals Infinity

lucid cairn
#

a^b multiplied c times

delicate torrent
glossy valveBOT
#

1 divided by 0 equals Infinity

lucid cairn
#

a is beinb multiplied b times

delicate torrent
glossy valveBOT
#

1 divided by 0 equals Infinity

lucid cairn
#

yh

delicate torrent
#

So it's just $a$ multiplied $bc$ times

glossy valveBOT
#

1 divided by 0 equals Infinity

lucid cairn
#

yh ok

#

so in this case

#

2 is being mutiplied 3 times which is being multiplied 2 times

#

yh?

delicate torrent
#

Which case?

lucid cairn
delicate torrent
#

Yup

lucid cairn
#

is there anything else i need to understand

#

for this

#

so how about this

#

x is being multiplied 3 times

#

and 2 is being powerd by 3 times?

blissful sail
#

But when you cube the whole thing, the cube gets distributed to both 2 and x^2

#

So you get $2^3 \times (x^2)^3$

glossy valveBOT
#

Ishmam

lucid cairn
#

aaa yes

blissful sail
#

Makes sense?

#

Now simplify the individual terms

#

2 cubed is 8

lucid cairn
#

yh thanks

blissful sail
#

And as you've seen, for x, we multiply the powers

lucid cairn
#

got it

blissful sail
#

Nice

lucid cairn
#

.close

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boreal flare
#

Une fonction (f) est majorée sur un intervalle (I) s’il existe un réel (M) tel que pour tout (x) dans (I), (f(x)\le M). Une fonction (f) est minoreée sur un intervalle (I) s’il existe un réel (m) tel que pour tout (x) dans (I), (f(x)\ge m). Une fonction est bornée sur un intervalle (I) si elle est à la fois majorée et minorée sur (I)

glossy valveBOT
#

StellarPhoton

boreal flare
#

can u guys explain it to me in english

#

: /

onyx glen
#

ok well ig here is a translation

#

let f : I -> R be a function. we say that:

  • f is bounded above on the interval I if there exists a real number M such that for all x ∈ I we have f(x) ≤ M
  • f is bounded below on the interval I if there exists a real number m such that for all x ∈ I we have f(x) ≥ m
    if your function is bounded above AND bouned below, then we just say it is bounded
boreal flare
#

ty, can u give me an example

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fallen jasper
#

Really hard

noble pivot
#

this just looks like tedious work, it doesnt look like any real math skills are being put to use

#

you just need to brute force it

narrow path
#

but that seems like about it to me

noble pivot
#

i'd do this with code, trial and error would take literal hours, but if you can only trial and error then i'd split the binary question into smaller parts

narrow path
#

there is quite literally 4,450,838 possible guesses

#

but the search space could be lowered heuristically

#

if you create standards for what could be a potential string of words

#

are you allowed to use code @fallen jasper

#

cause if you arent thats just screwed

torn sand
#

Can you paste the binary string here

narrow path
noble pivot
#

the way i'd do this manually is to just to find every possible letter for the first 5 characters

#

then i move one step and find all possible letts for the next 5 characters

#

its very tedious but its the only way i can think of

narrow path
raw kiln
#

the best unc meme

noble pivot
#

you dont have to count duplicates within the string of 5 as well since you shift by 1 character at a time, which helps i guess

#

either way, chatgpt says that the answer is: "questionwhatisoneplusone"

#

just lie and say you bruteforced it

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narrow path
#

but can we get a fact check on this

noble pivot
#

this is barely math tho

narrow path
#

fuh naw open your own channel bruh

noble pivot
torn sand
#

i would suggest enumerating a wordlist would be more feasible than enumerating all possible letter combinations

#

but code isn't allowed, so... 🤷

reef gale
#

Hi

torn sand
noble pivot
torn sand
#

actually?

noble pivot
#

either way, your best bet would to take the first 5 binaries, write down all the possible characters it can be (from left to right, no duplicates), then shift by 1 binary and repeat about 300 times

torn sand
#

"qu" strat might work lol

noble pivot
# torn sand actually?

sthisismurydsvineltpufverythoughtitwouldhelpstalnnlyymplequestionwhatisoneplusone
is what chatgpt got after 6 minutes of thinking lol

torn sand
#

using the fact that u always appears after q in english

noble pivot
narrow path
#

if you just spam rules like that it could help atleast

#

but the english language is notoriously stupid

torn sand
#

anyways i tried searching for common words like 'and' and 'the' but came up with nothing

noble pivot
#

if the teacher assigned you this i'd suggest just asking them to solve it

#

they seem to know something we dont

narrow path
#

Its funny cause even computing the amount of solutions is stupidly difficult cause its like the coefficient of some weird generating function (unless you can think of an easier way)

raw kiln
#

please close ticket @fallen jasper

#

this is not a talking ticket

narrow path
#

LETS GOO TROPOSPHERE

torn sand
#

how do you think you could extend this concept to the other letters?

#

on second thought, i dont think you can

marsh vault
noble pivot
torn sand
noble pivot
narrow path
noble pivot
#

this seems like a better problem for coding than for math

torn sand
#

another idea i have: questions usually use 5W1H -- who what when why where, and how.

you could try searching for those

narrow path
#

I thought of a computational approach which will probably work but its maybe a bit unsatisfactory due to it's involvement with code you just throw each possible solution into an NLP and perplexity score them and then just manually scan the top ranked ones

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reef crystal
#

Is A1 correct?

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reef crystal
forest trail
# reef crystal

Hi! In case 2, how did you know that a^(-k) * a^(k + r) was equal to a^r?

forest trail
# reef crystal

I think there is a way to prove this by induction without all of those cases. You should just prove that a^m * a^n = a^(m + n) by induction on n (keeping m fixed arbitrarily, you don't want to say something like m = -k because that overcomplicates things). Then repeat the same thing but prove that a^m * a^(-n) = a^(m - n).

#

Unless that was literally how the question was structured, in that case 🤷

prime pier
#

depending on where you start your induction, you may need to add n=0, etc., but that will blow it clean out the water and allow you to prove other exponent laws easier too

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verbal sky
#

not sure how to do b

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verbal sky
#

dont understand how this is true

lime ether
wide sundial
#

What does it mean if f(x) divided by (x+p) has remainder 9

sacred yarrow
#

@verbal sky Agree with what frosst mentioned, you should try to find the equation describing

f(x) divided by (x+p) has remainder 9

#

Here’s a simpler example

When 5 is divided by 3, the quotient is 1 and the remainder is 2

#

Try to find the relationship between these four numbers

lime ether
#

5(1)

wide sundial
verbal sky
#

9 = f(x) - (x+p) ?

verbal sky
sacred yarrow
#

The quotient is not always 1

#

It makes things much clearer in a word

verbal sky
#

.close

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sacred yarrow
#

Has your doubt been resolved? @verbal sky

verbal sky
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zenith haven
#

hello

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zenith haven
#

I am having an electrostatic quiz which I already solved but I want to check my steps. May anyone help me ?

neon basin
#

May we see the steps

zenith haven
neon basin
#

Thanks!

zenith haven
#

These are my steps I'd really appreciate your time to help

#

I think there is a mistake in region 1

#

that is my main concern actually

#

if u check here it says the outer shell is grounded.. should we have Electric field and Electric Potential in that first region as zero because of that ??

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@zenith haven Has your question been resolved?

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@zenith haven Has your question been resolved?

zenith haven
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.close

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reef crystal
#

Is A1 correct?

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@reef crystal Has your question been resolved?

reef crystal
#

<@&286206848099549185>

#

Anyone?

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rough tundra
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candid hazel
#

.open

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onyx glen
#

opening a channel just means sending your question directly in

candid hazel
onyx glen
#

anyway, progress?

candid hazel
onyx glen
#

hello. i don't remember you.

candid hazel
onyx glen
glossy valveBOT
candid hazel
#

i tried to change it to this

#

but idk it's validity

#

or what to do after this

#

<@&286206848099549185>

blissful sail
wise tartan
#

did you mean $\sum_{s=0}^n {n \choose r} \left(\sum_{r=0}^s {n \choose s}\right)$

glossy valveBOT
#

CherryMan

wise tartan
#

i mean yeah thats the same thing

wise tartan
queen flame
candid hazel
candid hazel
candid hazel
wise tartan
#

its correct

candid hazel
#

hmm

wise tartan
#

but what did you try after

blissful sail
wise tartan
#

wait wait

candid hazel
wise tartan
candid hazel
#

ohh

#

ohh wait

wise tartan
#

yeah the upper limit is s-1

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gilded forum
#

Help? I can’t multiply by nothing…

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sacred yarrow
#

@tall onyx

fast peak
#

wdym you cant multiply by nothing

scarlet pike
#

Perhaps can't solve by elimination

gilded forum
scarlet pike
#

So just use substitution

gilded forum
#

Oh!

#

Right

#

But not always substitution works

scarlet pike
#

It does

fast peak
#

multiply by 3?

scarlet pike
#

Given the system has a solution of some kind

gilded forum
#

Something like this

cerulean trellis
scarlet pike
#

Yeah elimination is much easier in this case

gilded forum
#

Where

#

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gilded forum
#

Ok ik

#

I wanted to do that

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gilded forum
#

,w 1/3 * 3/2

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gilded forum
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.close

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royal dew
#

find the bounded area

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royal dew
#

,w integrate 2-1/(sqrt(1-x^2)) from x = -sqrt(3)/2 to x = sqrt(3)/2

royal dew
#

is this the right answer

#

,w plot 1/(sqrt(1-x^2))

royal dew
full forumBOT
#

@royal dew Has your question been resolved?

royal dew
#

<@&286206848099549185>

queen flame
#

yeh looks good

royal dew
#

.close

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daring patrol
#

If sin(θ+Φ)=2sin(θ-Φ)
prove that tanθ=3tanΦ

daring patrol
#

I am assuming expand and solve it but I am not sure ...

burnt turret
glacial stream
daring patrol
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# daring patrol If sin(θ+Φ)=2sin(θ-Φ) prove that tanθ=3tanΦ
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
daring patrol
glacial stream
#

!showyourwork

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#

Show your work, and if possible, explain where you are stuck.

daring patrol
#

Oh wait , just solved it correctly
Just a small mistake in calculation

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Ty!

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left moon
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left moon
#

Could someone please check my work? There is no answer for me to check with in the back of the textbook

rare dock
#

,w partial fraction 3/(x^4+x)

rare dock
#

yes it looks right

left moon
#

Yay

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Thank you

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digital arch
#

How do I do the equal volume part

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digital arch
#

I already did ts

#

oops forgto this

hoary ember
digital arch
#

is it 512^1/5

hoary ember
#

yeah

digital arch
#

alr

#

thanks

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digital void
#

Hello. so for δ, i had to express a sentence using "implies" into a sentence using only "or" or "not". is this the right way to do it? i could definitely do the entire board thing too and simplify it but our prof asked only for different expression, not simplified ones

digital void
#

,rccw

glossy valveBOT
foggy vapor
#

Its you kekwait

digital void
#

hi lex

#

im writing in 4 days man

foggy vapor
digital void
#

okeoke thank you

#

.solved

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maiden vapor
#

You’re welcome fijo

foggy vapor
nimble crane
maiden vapor
foggy vapor
maiden vapor
#

One might say aura.

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snow mural
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snow mural
#

How to solve b)

#

<@&286206848099549185>

queen flame
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# snow mural <@&286206848099549185>

Please only use the <@&286206848099549185> ping once if your question has not been answered for 15 minutes. Please do not ping or DM individual users about your question.

forest trail
hidden harbor
# snow mural

its a product of 4 things, and result is positive or 0

forest trail
#

In other words, can you translate the inequality into english?

hidden harbor
#

so either one of them is 0, or an even number of them is negative

forest trail
snow mural
#

But it’s in the question

forest trail
#

Well,

snow mural
#

I just want to solve b

forest trail
#

Both part a) and part b) has the same polynomial described, right?

next cedar
#

you have the graph, and also, remember the keyword hence.

queen flame
#

when is the graph above x axis and crosses it?

next cedar
#

if you see that keyword, consider using whatever you have proven in the subquestions prior

snow mural
#

Ohhh so I need to check graph

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@snow mural Has your question been resolved?

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signal solar
#

i feel like all are true so im confused

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rapid rain
#

Hint: ||what does 6/x^3 integrate to||

fiery cedar
#

@rapid rain <@&286206848099549185>

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fiery cedar
#

Thanks

rapid rain
signal solar
rapid rain
signal solar
#

yep

rapid rain
#

now we're good

#

yeah that's all antiderivatives

signal solar
#

ok but that hint i still not sure

fiery cedar
#

Help me too guy's😭 tomorrow is my exam i am cooked

rapid rain
signal solar
#

i think it converges because of p series test

#

if that counts

rapid rain
#

p series test?

#

I think you're confusing with different bounds

modest obsidian
#

p series is only for 1 to inf

signal solar
#

ah

modest obsidian
#

but you should realise

rapid rain
#

there is a p test for 0 to 1

#

but it's very much different

modest obsidian
#

what happens to p series from 0 to 1

signal solar
rapid rain
#

imagine, instead of integrating between 0 and 1

#

we integrate between a and 1, where a > 0 gets smaller and smaller

#

that's the definition of an improper integral

#

so

#

$\int_a^1 \frac{6}{x^3}dx$

glossy valveBOT
#

Raphaelisius Maximus MMIII

rapid rain
#

This is a proper integral

#

so what does FTC tell you?

rapid rain
signal solar
modest obsidian
#

fundamental yada yada

signal solar
#

ah

#

lols

modest obsidian
#

so what do you think?

#

from the fundamental theorem of calculus, what do you get

signal solar
#

evaluate antiderivate from 1-a?

modest obsidian
#

uh sure

#

what would $\int_{a}^{1}\frac{6\mathrm{d}x}{x^3}$ look like then?

glossy valveBOT
#

parabolicinsanity

modest obsidian
#

the point is that we can then look at the case where a approaches 0

signal solar
#

-3/1^2 - -3/a^2

modest obsidian
#

yes

#

!!

#

now what happens when a approaches 0

signal solar
#

that term pretty much turns into infinity

#

divides by very small number

modest obsidian
#

so it would mean that the integral is

#

divergent

signal solar
#

i see

modest obsidian
#

so claim 2 is false!!!

#

huzzah!!!

#

how for the actual integral

#

uhh

rapid rain
#

let em think

signal solar
#

well since claim 1 is true

#

then i assume by comparison test then it would be divergent

rapid rain
signal solar
#

oh well

#

no

rapid rain
#

so we can't use claim 1 to prove convergence or divergence

signal solar
#

so do we have to make a new claim

rapid rain
#

yes, and before we do that, a quick point on "p tests"

#

You've probably seen how $\int_1^\infty \frac{1}{x^p}dx$ converges if and only if... what?

glossy valveBOT
#

Raphaelisius Maximus MMIII

signal solar
#

p>2 or something like that

rapid rain
#

that's not exactly correct

signal solar
#

p>1

rapid rain
#

yes

#

you remember why? It's pretty much what we did here

#

when $p > 1$, $\frac{1}{x^p}$ integrates into $-\frac{p-1}{x^{p-1}}$

glossy valveBOT
#

Raphaelisius Maximus MMIII

rapid rain
#

and so, plugging "x = infinity", there's no problem

#

because 1/infinity is 0

signal solar
#

right

rapid rain
#

so it's actually "constant/0" when x = infinity

#

and diverges

signal solar
#

Yup

rapid rain
#

and when p = 1, it's log

#

which diverges too

signal solar
#

Right

rapid rain
#

so that's the p-test around infinity

#

when we're around 0

#

the integrations we make are still valid

#

but we're worried about "x=0", not "x= infinity"

rapid rain
#

which diverges

#

and p < 1 with x = 0 gives us constant/infinity

#

converges

#

(p = 1 still gives us log, and log(0) also diverges)

#

any questions about that or does that make sense?

signal solar
#

It makes sense

rapid rain
#

alright

#

so

#

$\int_0^1 \frac{1}{x^p}dx$ converges if and only if $p < 1$

glossy valveBOT
#

Raphaelisius Maximus MMIII

rapid rain
#

so, if we want to use comparison test around 0

#

In our case

#

What should we keep in the denominator

signal solar
#

x^1/3

rapid rain
rapid rain
#

now, the integral linked to this function is convergent (p test around 0)

#

so using comparison test, the original integral is convergent

#

If you want to take a bonus problem: is $\int_0^\infty \frac{5-\sin x}{x^{1/3}+x^3}dx$ convergent?