#help-0

1 messages · Page 524 of 1

mossy locust
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(ln | ln (infinity) | ) - (ln|ln(2)|)

buoyant saddle
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yep

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which is

mossy locust
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so then basically it doesnt matter anymore because the natural log of infinity is infinity and the natural log of that also happens to be infinity and it doesnt really matter what we decide to subtract from that at that point because hey its infinity it doesn't really care what we subtract from it as long as its not another infinity

buoyant saddle
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yep

mossy locust
buoyant saddle
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your classmates are fucking cornballs

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it diverges sir

mossy locust
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do you want to hear what this guy told me

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right quick because he had ME fucked up

buoyant saddle
#

,w \sum_{n = 2}^{\infty} \frac{1}{n \ln n}

mossy locust
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what is this

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does it do math

buoyant saddle
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it does

mossy locust
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I've never been in this server before I was really twisted and had to come make sure that I wasn't crazy

patent vale
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its crazy some of yall are just unaware of wolfram

mossy locust
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but they were trying to tell me that you could say that it converged by comparison with

1/n^1

because 1/n * ln (n) is smaller than the function but hey guys guess what 1/n^1 doesn't converge so it doesn't really matter if its smaller thats true and great for it but it still doesn't make 1/n^1 converge

buoyant saddle
mossy locust
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I appreciate the help there

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It seemed pretty straightforward to me

buoyant saddle
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you're welcome

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it was

mossy locust
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Little integral test

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But now the answer key and my classmates are wrong

buoyant saddle
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typical

mossy locust
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I love high school

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we almost out

buoyant saddle
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nah lol

mossy locust
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are you a genius how does this server work

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cause chat gpt not very smart so I had to come over here

buoyant saddle
#

i just volunteer as a hobby when im bored

mossy locust
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that's super cool

buoyant saddle
#

my brain isnt working rn

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cant do my own math

mossy locust
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valid

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do other peoples math

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what math are you in

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like what is the highest course you've taken

buoyant saddle
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real analysis

mossy locust
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I don't want to take up too much of your time you've prolly got other people to help

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real analysis

buoyant saddle
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we somehow went from completeness axiom to convergence of fourier series and baire category theorem in the same semester

mossy locust
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how many rings in the ladder would that be above a calc 2 class (not what I'm in) im in Calc BC which would be kind of part of Calc 2 but I'm not convinced there doing a good job at actually teaching much of it

buoyant saddle
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i took calc bc last year

mossy locust
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(please make it stop)

buoyant saddle
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so like if youre planning on doing a math major and go to a pretty good institution then you might do something similar

mossy locust
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I'm planning to study mechanical engineering

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so

buoyant saddle
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ok then you dont have to cry

mossy locust
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🎊

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I don't

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this is good news

onyx swallow
buoyant saddle
mossy locust
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I don't think that I do

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so ME students don't have to take that stuff?

buoyant saddle
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like tell me how we went from induction proofs on the first homework to fucking fourier analysis

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😢

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metric spaces wasnt too bad

mossy locust
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I appreciate the help

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I might be back this very evening

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Idk why but I'm still not convinced its so annoying that the answer key is wrong

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this is the second time

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can we do a quick taylor polynomial

buoyant saddle
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it diverges my friend

onyx swallow
mossy locust
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but like how did my teacher even think that it didn't

buoyant saddle
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i cant imagine what that shits going to be

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same professor too

mossy locust
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alright so this taylor polynomial is going to be 3rd degree of

f(x) = ln (3-x)

about x=2

onyx swallow
buoyant saddle
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i will need it

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im going to guess hes going to want to cover big rudin

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😭

mossy locust
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f(x)=0 bye bye

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

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

f^(3) (x) = -2(3-x)^-3

buoyant saddle
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i hate this book enough already

buoyant saddle
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first year course btw

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take me back to sequences 🙏

mossy locust
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then plug in at each of those for x=2 so

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

so write the taylor polynomial

-(x-2) - 1/2 * (x-2)^2 - 2/3! * (x-2)^3

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the answer key says that the sign of the 2nd degree is posotive

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but I believe that the chain rule while taking the derivatives keeps it negative

buoyant saddle
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why are we doing this?

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integral test is perfectly fine here

mossy locust
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nooo its a whole different question

buoyant saddle
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whats the question

mossy locust
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am I supposed to end the thing and start another sub thing

buoyant saddle
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nah you're chilling

buoyant saddle
mossy locust
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come again

buoyant saddle
#

common taylor series

mossy locust
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yeah I hate to say that I don't

buoyant saddle
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ln(3 - x) = ln(1 - (x - 2))

mossy locust
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yeah so then just plug in

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I know that I should be able to recognize them that will help for the test as well

buoyant saddle
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the taylor series for ln(1 - x) is quite common

buoyant saddle
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i mean

mossy locust
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sinx cosx e^x

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lnx I believe

buoyant saddle
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tbf like ap calc only cares about sinx, cosx, e^x, and geometric

mossy locust
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I'd have to break out the notes

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yeah

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I'm not sure if we hit lnx

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but If I got the taylor series for ln(1-x) then how do you account for the 3

buoyant saddle
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they said about x = 2 for a reason

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the taylor series is -x^n/n

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so just put x --> x - 2

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-(x - 2)^n/n

mossy locust
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therefore all negatives

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the answer key says that the third term of the taylor series is

  • (x-2)^2/2
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but it is negative correct

buoyant saddle
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if my memory is correct it should be all negative

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lets derive it i guess

mossy locust
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yeah I thought so because even if you do it by hand the chain rule keeps the derivatives negative

buoyant saddle
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$\frac{1}{1 - x} = \sum_{n = 0}^{\infty} x^n$

ocean sealBOT
buoyant saddle
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so this holds for |x| < 1

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we can integrate both sides and this will indeed hold for |x| < 1

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$-\ln(1 - x) = \sum_{n = 0}^{\infty} \frac{x^{n + 1}}{n + 1} \implies \ln(1 - x) = \sum_{n = 1}^{\infty} -\frac{x^n}{n}$

ocean sealBOT
buoyant saddle
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then letting x go to x - 2 we get

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$\ln(3 - x) = \ln(1 - (x - 2)) = \sum_{n = 1}^{\infty} - \frac{(x - 2)^n}{n}$

ocean sealBOT
mossy locust
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always negative

buoyant saddle
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yep

mossy locust
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yeah this teacher has me twisted

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but ay life rolls on

buoyant saddle
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your teacher is fucking buns bro

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hate to break it to you

mossy locust
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seems as though I know semi whats going on

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bro reads from the text book and thats about all

buoyant saddle
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did you follow the derivation?

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its literally a one liner

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as an exercise, try to deduce the taylor series for ln(1 + x) given the taylor series for ln(1 - x)

buoyant saddle
mossy locust
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but then I have these people that think they're geniuses who are using the comparison test in a way that doesn't even make any sense because they are trying to compare a diverging series to a smaller series and saying that it converges

buoyant saddle
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they are not geniuses sir

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almost no one is tbf

mossy locust
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on baby

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but I tried to tell them hey I think that doesn't make any fucking sense and they said no

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so

buoyant saddle
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everyone thinks they're of above average intelligence lmao

mossy locust
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that's how I got here I thought there's gotta be someone out there better at math than me who can say hey no these guys are a bunch of morons

mossy locust
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and I got a migraine right now but the mid term is tomorrow so

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really no chance to wait now is there

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anyways

buoyant saddle
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midterm?

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its may

mossy locust
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I guess

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final term

buoyant saddle
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you have ap exams in a week

mossy locust
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end of term

buoyant saddle
#

ugh

mossy locust
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that one

buoyant saddle
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i lowkey miss high school now bro 😭

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ap week was peak

onyx swallow
buoyant saddle
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i know

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thats the point

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😭

mossy locust
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we trying to avoid the rigor

mossy locust
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wait no

buoyant saddle
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calc bc is fun because you dont have to think

buoyant saddle
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yea

mossy locust
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would you not just flip the signs

buoyant saddle
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you would

mossy locust
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ohh no cause the x is negative

buoyant saddle
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ln(1 + x) = ln(1 - (-x))

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take x to -x

mossy locust
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wait a minute

buoyant saddle
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you get an extra (-1)^n

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which you can combine with the other - to get (-1)^{n + 1}

mossy locust
#

what do you mean by take x to -x

buoyant saddle
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replace x in our known formula for ln(1 - x) with -x

mossy locust
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yes

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giving ln (1 - (-x))

buoyant saddle
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but also in the series representation

mossy locust
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but can you not just say then ln (1+x)

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yeah I might be fried I didn't pay attention too well this last quarter here

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is there a video you'd recomend for subbing in things to taylor series

buoyant saddle
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uhhh

mossy locust
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or just watch a video

buoyant saddle
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im not sure, khan academy might have some

mossy locust
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bet

buoyant saddle
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bprp maybe?

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let me find some

mossy locust
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perfect

buoyant saddle
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yea id just watch khan academy

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i think its valuable to understand the nitty gritty of what these things are really telling you, like what really is a power series but in terms of computational problem you just need to do more problems to see the patterns

mossy locust
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yeah I got you

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I defintely haven't done the reps this quarter

buoyant saddle
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exercises are the most important part of math

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i laugh at people when they say they read math books then mention they dont do the exercises

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like fym you read it

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it isnt a novel

mossy locust
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it's obvious but especially senior year its easy to be lasy and not do them

buoyant saddle
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ya know what they say

mossy locust
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damn kids

buoyant saddle
#

what you read you forget, what you do you remember

mossy locust
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I don't think my teacher did any of this

buoyant saddle
#

since youre going for mech e

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you save yourself two semesters

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hella money

mossy locust
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we will see how I do

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I'm definitely going to take studying seriously I've got about 2 weeks before the test

buoyant saddle
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dialed

mossy locust
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yessir I've got 6 more questions on these MCQs to get through here tonight I'm going to get back to cracking

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I appreciate the help

buoyant saddle
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no worries

mossy locust
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I'll spin back if I get lost again or the answer key is wrong again

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likely

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how do I close the chat for rn

buoyant saddle
#

type .close

mossy locust
#

TYSM

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.close

lone heartBOT
#
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lone heartBOT
#
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alpine sable
#

guys what the hell is this formula
i know of area of surface revolution but that contains 2pi
and this one doesn't
so that means we got height multiplied by length
thats area for sure
but not revolved i suppose?
why not just int a to b f(x) dx

unique dune
#

Lien integral??

alpine sable
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ohhh wth

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can u show like a proof that leads to that

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or link to smth

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i know of arc length

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and area forced my revolving around the

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arc of a curve

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when i saw this problem my first thought was

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its just area under the f(x)

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but hell no

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its not but should be solved with line integral

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and im not very sure about that

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why is that

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waitttt if we don't revolve the arc but rather just multiply f(x) with ds

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that would be area without revolution

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is that formally said line integral?

unique dune
#

Line integral is the area of the surface formed by the line to the xy plane

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In the simplest

alpine sable
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so thats just

alpine sable
#

omg

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i was thinking it should be like going to be in same direction

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so it seems like how line integral is different from area under the graph is that

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it is over the plane

lone heartBOT
#

@alpine sable Has your question been resolved?

#
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midnight gale
lone heartBOT
midnight gale
#

so i alr know that triangle klh in iscoscles

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and kln is 45 degrees

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but idk how to go one from there

lone heartBOT
#

@midnight gale Has your question been resolved?

midnight gale
#

no one answered

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bruh

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<@&286206848099549185>

#

DJKSL;AFJLK;SAFDASFASF

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hel p ehlp

floral fiber
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yo

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do u agree LKN = MNK?

midnight gale
#

yayy help

midnight gale
floral fiber
#

So i can draw like this?

midnight gale
#

yeah

floral fiber
midnight gale
#

yeah i drew like that too

floral fiber
#

If I put A, do you agree KH = AN?

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can u find KH?

midnight gale
#

yeah

midnight gale
floral fiber
#

With KH, can you find HN?

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I highlighted for you to see the triangle in focus :0

echo belfry
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Lh is root80

midnight gale
floral fiber
#

yee

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so from there, what trigo rule cna u use?

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to find ur LKN

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:0

midnight gale
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im not sure

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oh wait

#

lkn

echo belfry
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It should be tan inverse root80/5

midnight gale
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thats 45 degrees

floral fiber
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HN = ?

midnight gale
#

8

echo belfry
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8

floral fiber
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by pyth, LH = sqrt(LN^2 - HN^2)

echo belfry
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Lh is 5

floral fiber
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So if u put in the numbers, u can find LH = 5

midnight gale
#

yeah lh is 5

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i found that

echo belfry
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So 45

floral fiber
#

from there if both lenghts are 5

echo belfry
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Deg

floral fiber
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the angle is 45

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yee

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:]

midnight gale
#

OHHHHHH

#

oops

#

.close

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junior lagoon
#

why is this question wrong? the practice test explained it but it still doesn't make sense to me

vale wigeon
#

do you get why kj = -45

junior lagoon
#

yes

lone heartBOT
#

@junior lagoon Has your question been resolved?

junior lagoon
#

.close

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fervent jungle
#

A hydraulic system has a mechanical advantage of 2.5 and is 90% efficient. Calculate the diameter of the input cylinder if the diameter of the output is 30mm

fervent jungle
#

can anyone do engineering

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kinda confused on this

lean tangle
#

So MA_ideal=n/MA

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Then you need to calculate the area of the input piston.

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Finally use this formula:
MA_ideal = Ao/Ai

lean tangle
#

And use that to find the diameter.

fervent jungle
#

aight

lean tangle
#

Yep.

fervent jungle
#

so i got 18mm

#

.close

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#
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lean tangle
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late fjord
lone heartBOT
late fjord
#

ik im supposed to use completing the square but ym ans is kinda weird

cobalt oriole
#

like

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always real?

late fjord
#

what

cobalt oriole
#

oh i translated it

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brb

cobalt oriole
#

is it uh

late fjord
#

.close

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late fjord
#

no but i got the ans alr, appreciate the effort

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devout helm
#

Is this correct so far?

lone heartBOT
vale wigeon
#

nope

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only the first step of factorizing the bottom is correct

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it looks like there's a list of steps on the paper just above the example you're doing

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are you following that or not?

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@devout helm

devout helm
vale wigeon
#

ok, no, hold on.

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can you type out what step 1 says to do

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just type it out exactly as it is written on your paper

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do nothing else except for what i ask

devout helm
#

step1. factor the denominator of the rational expression into linear factors

vale wigeon
#

ok

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now answer me this:

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have you already done step 1?

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your answer must be "YES, I have done it." or "NO, I have not yet done it."

devout helm
#

yes

vale wigeon
#

ok

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now type out what step 2 says to do

devout helm
#

step2. write one partial fraction for each of these factors, with unknown constant numerators e.g A and B

vale wigeon
#

ok

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have you already done step 2?

devout helm
#

I tried but you said its incorrect

vale wigeon
#

what should the numerators be?

devout helm
vale wigeon
#

no

vale wigeon
#

it says something about what you should put in the numerators

devout helm
#

the first is 1(x+3)

vale wigeon
#

no

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read. the step.

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do you see where the word "numerators" appears in it

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do you see it? yes or no.

vale wigeon
#

right here.

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do you see it now? yes or no.

devout helm
#

yes

vale wigeon
#

ok

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tell me now:

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the step tells you what the numerators should be.

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what should they be?

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not "what are they", not "what did you write on the paper".

devout helm
#

I dont know, I really dont know Im sorry

vale wigeon
#

dude

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i am literally just asking you to read one sentence

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i don't know if you're overthinking yourself into oblivion or having a massive blindspot or brain fart or what

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but i am not asking you to do anything complicated at all

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this is just a reading comprehension thing

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step2. write one partial fraction for each of these factors, with unknown constant numerators e.g A and B

devout helm
#

oh its A and B

vale wigeon
#

third time's the charm.

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ok, now write down the fractions as the step says.

devout helm
#

but there's only one constant here

vale wigeon
#

write one partial fraction with the letter A for its numerator and the other with the letter B for its numerator.

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i think maybe you should come back to this problem when you are less brain-fogged because you are struggling with following simple instructions at the moment

devout helm
#

NO

vale wigeon
#

ok yeah yknow what good luck i guess
ive had enough of this

devout helm
zinc bolt
#

The reason it isn't

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is because

crisp turtle
zinc bolt
#

$\frac{1}{3} = \frac{1}{3} + \frac{0}{6}$ but this doesn't mean that $\frac{1}{3} = \frac{1}{18}$

ocean sealBOT
#

@zinc bolt

devout helm
#

oh so how do I go about doing this

tulip bone
#

😭

tulip bone
#

on how to do partial fractions

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start with that

zinc bolt
#

You have the procedure just above the question

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Start by doing that

devout helm
zinc bolt
#

$\frac{1}{(x + 2)(x + 3)} = \frac{A}{x + 2} +\frac{B}{x + 3}, A, B \neq 0$

tulip bone
#

Wait wait

zinc bolt
#

This is step 1

tulip bone
#

I dont think he knows how to do

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fraction addition

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😭

ocean sealBOT
#

@zinc bolt

zinc bolt
devout helm
tulip bone
zinc bolt
ocean sealBOT
#

@zinc bolt

devout helm
zinc bolt
#

Note that if $A = 0$ or $B = 0$ your solution will be invalid

ocean sealBOT
#

@zinc bolt

devout helm
#

so I make it into one fraction?

zinc bolt
#

Sure?

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Try doing it and I'll tell you if you're wrong

tulip bone
#

poor Ann

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aint being paid enough for ts 🥀

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😭

#

Just to put it out there btw $\frac{A}{B} + \frac{C}{D} = \frac{AD+BC}{BD}$

devout helm
ocean sealBOT
zinc bolt
tulip bone
zinc bolt
#

i.e.

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$$\frac{Ax + Bx + 3A + 2B}{(x + 2)(x + 3)} = \frac{1}{(x + 2)(x + 3)}$$

ocean sealBOT
#

@zinc bolt

tulip bone
#

yes

#

hiten what math are u doing btw

devout helm
zinc bolt
zinc bolt
tulip bone
zinc bolt
#

I am at presnet BTech student

tulip bone
tulip bone
zinc bolt
#

I didn't do anything complicated here so far

tulip bone
#

$\frac{A}{B} = \frac{C}{B}$ is the same as $A = C$

ocean sealBOT
tulip bone
#

but like

zinc bolt
#

if $A, B, C \neq 0$

ocean sealBOT
#

@zinc bolt

tulip bone
#

i remember u asked a

#

combinatorics question

#

yesterday

zinc bolt
#

Oh yea

#

I am doing an optional course on Combinatorics

tulip bone
#

Did u get ur solution for that-

zinc bolt
#

Yes

tulip bone
#

Gotchu

#

That math seemed TOUGH

#

What did u do before btech to even understand that

#

😭

zinc bolt
#

Ok, if you wanna connect please dm me, let's not hijack this help channel for catch up chats

zinc bolt
#

@devout helm you there?

devout helm
zinc bolt
#

Did you try solving that equation?

#

How far did you get?

devout helm
zinc bolt
#

You can state assuming $x \neq -3, x \neq -2$ and then proceed

ocean sealBOT
#

@zinc bolt

zinc bolt
#

This assumption is fine because without this assumption the denominators are invalid

devout helm
zinc bolt
#

It means that x's value can't be -3 or -2 because then the fracion would have a 0 denominator which is invalid

tulip bone
#

i don't think he needs to include all that yet

#

he's merely doing partial fractions

#

😭

#

but you are right either way

#

Basically that for ex, if you put in -2 and -3, you'll get a zero in the denominator since (-2+2) x (-3+3) = 0 and u can't have 0 in denminator

devout helm
tulip bone
#

I genuinely don't remember doing partial fractions

tulip bone
#

So yes, u are

devout helm
#

so Ax+3A+Bx+2B = 1?

zinc bolt
#

yes

#

Keep going

devout helm
#

Ok so I’m at this point now

zinc bolt
#

Have they not taught you how to find and use 0s of an equation?

devout helm
#

I guess not

zinc bolt
#

Hm...

zinc bolt
devout helm
#

yeah

zinc bolt
#

Yea put $x = -3$ first and then once you have one variable for the other put $x = -2$

ocean sealBOT
#

@zinc bolt

devout helm
#

but are you continuing from the step that I've done or

zinc bolt
#

Yes

devout helm
#

so whats the purpose od doing this then

zinc bolt
#

RN RN there is none

#

but which grade are you in

devout helm
zinc bolt
#

?

devout helm
#

its like a college

#

and I'm freshmen

zinc bolt
#

Oh ok

#

You'll require this for your calc-course

devout helm
#

calculus?

zinc bolt
#

Are you aware of what calculus is?

#

Yes

devout helm
zinc bolt
#

Yea this is something we need to do for integration a lot

devout helm
#

I'm taking engineering as my course next year and I definitely need calculus

zinc bolt
#

Yea

#

that's prolly why you're being taught this

#

GL for your future

devout helm
#

wbu?

zinc bolt
#

Let's do that in dms

#

!done

lone heartBOT
#

If you are done with this channel, please mark your problem as solved by typing .close

devout helm
#

.close

lone heartBOT
#
Channel closed

Closed by @devout helm

Use .reopen if this was a mistake.

#
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After 15 minutes, feel free to ping <@&286206848099549185>.
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raw jetty
#

the adjoining figure shows two intersecting chords in a circle, with B on minor arc AD.
Suppose that the radius of the circle is 5, that BC = 6, and that AD is bisected by BC. Suppose
further that AD is the only chord starting at A which is bisected by BC. It follows that the
sine of the minor arc AB is a rational number. If this fraction is expressed as a fraction m/n
in lowest terms, what is the product mn?

raw jetty
#

idfk status 1

lone heartBOT
#

@raw jetty Has your question been resolved?

crisp turtle
#

i wont go to sleep tonight till i solve this

verbal blaze
#

me neither XD

crisp turtle
#

ok this diagram really sucks doesnt it

#

the radius of the circle is 5 but the chord BC is 6?

#

it should be more like 9

verbal blaze
#

missing a "(not drawn to scale)" XD

#

really, the system only has 2 degrees of freedom

lean tangle
#

I think I've seen this question before.

#

AIME question.

#

If not mistaken.

empty mason
lean tangle
#

Was one of the question I learnt when I was preparing for national math contest.

#

Sorry not Olympic.

#

I'm not good enough for that.

empty mason
crisp turtle
#

clearly im not smart enough to solve this

lean tangle
#

I think I recall one of them that uses coordinate geometry.

crisp turtle
#

my answer is

#

its one of 5, 10, 15, and 20

lean tangle
crisp turtle
lean tangle
#

Hint.

crisp turtle
#

sobbing

lean tangle
#

It's larger than 100.

#

XD

#

Lemme have a look.

empty mason
lean tangle
crisp turtle
#

lmao

lean tangle
raw jetty
crisp turtle
#

my method of solution was

lean tangle
empty mason
raw jetty
#

aw cmon trig really

crisp turtle
#

its the sine of an arc in a circle with radius 5
thus it must be one of 1/5 2/5 3/5 4/5

lean tangle
empty mason
lean tangle
#

There are 8 solutions in total.

raw jetty
#

oh i thought i reached the bottom

empty mason
crisp turtle
lean tangle
#

That one has no trig.

empty mason
lean tangle
raw jetty
#

whats a locus

empty mason
empty mason
lean tangle
lean tangle
empty mason
#

Btw the first solution is easiest to follow in my opinion. Just need to know your sine angle subtraction formula in hand and your hood

#

And btw I’m bad at trig

lean tangle
lean tangle
#

+1

empty mason
# lean tangle Broski

I unfortunately cannot rely on trig in olympiads, especially memorising formulas. But I use it when times are needed

lean tangle
#

Yeah true.

#

I faced a trig question in my most recent competitions.

raw jetty
#

why is sin(AOB)=x/5

lean tangle
#

1?

raw jetty
#

7

#

oh wait nvm

#

ok i see, thank you!

#

.solved

lone heartBOT
#
Channel closed

Closed by @raw jetty

Use .reopen if this was a mistake.

#
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After 15 minutes, feel free to ping <@&286206848099549185>.
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latent needle
#

Can somebody Substantiate why the two squares are squares (Pythagoras)

edgy hemlock
#

Does he mean the inside and outside sqaures?

tulip bone
#

the outer square was made from the inside square

latent needle
lean tangle
#

Yeah

edgy hemlock
#

Both have angles of 90°

lean tangle
#

Well I guess we need to prove it.

edgy hemlock
#

Yeah

lean tangle
#

Since the inside square is equals to 90.

edgy hemlock
#

We can prove that through the • angle

#

It’s 90°

lean tangle
#

The exterior angle • is also 90°

#

So alpha+beta+90=180

Which leads to alpha+beta=90°

edgy hemlock
lean tangle
lean tangle
latent needle
latent needle
lean tangle
edgy hemlock
lean tangle
#

Since alpha+beta is 90°

#

We know that it's a right angle

#

Do it on all sides.

#

You get 90° at all vertices.
Or corner.

#

And that's how we know that it's a square.

latent needle
#

Okay and how can I get the area of the outer square ? (2 different ways how to calculate)

edgy hemlock
#

Actually the angles not the areascatglasses

#

Oh i thought the 2kgod was talking mb

lean tangle
lean tangle
#

After the OP talked.

#

XD

#

Or a²+b²

lean tangle
latent needle
#

Okay thank you guys !

lean tangle
edgy hemlock
latent needle
#

How can I close this chat ?

lean tangle
lean tangle
edgy hemlock
#

Bruh

lean tangle
#

The second time.

#

XD

edgy hemlock
#

Doesn’t he need to sqrt that

lean tangle
edgy hemlock
lean tangle
#

c²=area of large square.

edgy hemlock
#

Actually yeah

lean tangle
#

So why hassle to square root and square it again?

edgy hemlock
#

To find the length of the side to square itsully

lean tangle
#

@latent needle

#

Still here?

edgy hemlock
latent needle
#

Yes

lean tangle
edgy hemlock
#

If you dont have more questions use .close

lean tangle
#

XD

latent needle
#

.close

lone heartBOT
#
Channel closed

Closed by @latent needle

Use .reopen if this was a mistake.

lean tangle
#

.reopen

#

Bruh

#

I wanna reopen it.

#

.reopen

latent needle
#

Should I?

edgy hemlock
#

Send a msg in a few

#

It will reopen

edgy hemlock
lean tangle
#

Okay.

vale wigeon
lean tangle
#

So.

#

How do I send question?

edgy hemlock
vale wigeon
lone heartBOT
#
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After 15 minutes, feel free to ping <@&286206848099549185>.
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verbal timber
lone heartBOT
verbal timber
#

but the answer is not a unit vector

vale wigeon
#

yeah it's BS

#

this is a perfectly serviceable proof that no such vector exists

#

precisely because the only vector you found that could possibly satisfy everything here actually violates the requirement of "unit vector"

winter light
#

But can't the vector be scaled and still have the same angle wrt those two vectors?

vale wigeon
#

the angles are wrong anyway because we assumed in the angle calculation that |r| = 1

#

when it isnt

verbal timber
vale wigeon
#

these four constraints:

  • be in the XY plane
  • be a unit vector
  • make angle 45° with i+j
  • make angles 60° with 3i-4j
    are impossible to satisfy all at once
verbal timber
#

the three conditions dont meet

vale wigeon
winter light
tight pier
#

the scaling doesnt change the vectors angle to another

winter light
#

Yeah exactly

#

So why can't we scale the result so that it becomes a unit vector?

verbal timber
stone coyote
#

idts there exists a vector which make 45 with i+j and 60 with 3i-4j

#

like try to draw it out

#

45 with i+j means either x or y axis
and 3i-4j is making -37 with x

winter light
#

Yeah indeed

#

The problem is not being a unit vector, just those incompatible angles

stone coyote
#

yeah

tight pier
verbal timber
#

,w calculate angle bw (13/sqrt(170), 1/sqrt(170), 0) and (1,1,0)

tight pier
#

the vector being not a unit vector shows that it's not possible because it's a contradiction to the assumption we made

verbal timber
#

thanks everyone

#

.close

lone heartBOT
#
Channel closed

Closed by @verbal timber

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#
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After 15 minutes, feel free to ping <@&286206848099549185>.
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jolly jasper
#

Just a quick question. If A = {1,2,3} and R = {(1,1), (2,2), (3,3), (1,2)}, then is the relation R on A transitive?

winter light
#

What do you think?

jolly jasper
#

I don't think it is.

#

so... am i correct?

tight pier
#

Can you reason why tho

jolly jasper
#

there's no (2,3)?

winter light
#

I would have said it is

jolly jasper
#

i kind of understood the concept but when i put the question into chatgpt and gemini it says the relation is transitive.

jolly jasper
winter light
#

Because for every element (1, 2 and 3) this condition is satisfied:

aRb and bRc => aRc

jolly jasper
#

but i dont see bRc

winter light
#

At least that's how implications in logic (truth tables) work

winter light
jolly jasper
#

I don't get it. if bRc then shouldn't there be (2,3)?

winter light
#

If it's not there you can't make any conclusion

#

If (2, 3) was there (but not (1, 3)) then it would not be transitive

jolly jasper
#

but we can prove using (1,2), no?

#

ohh wait. i get it now.

winter light
jolly jasper
winter light
#

Again, I would like some confirmation by someone a little bit more fond of this

tight pier
#

ok i see my mistake

jolly jasper
#

???

tight pier
#

ok let me ask you this why did you say (2,3)

jolly jasper
#

bRC.

#

we have aRb so i thought we only needed bRc but then i realised that we would also need aRc.

tight pier
#

aRb and bRc are both required for you to look for transitivity, if bRc cannot be found then it's pointless to investigate aRc

#

for example for (1,2) you cannot find another pair like (2,3) therefore you stop there

#

for (2,2) it works and it implies (1,2)

jolly jasper
#

that's what im saying but chatgpt and gemini say that R is transitive so is the AI wrong?

tight pier
#

no what i am saying is just because there isnt (2,3) doesnt mean it's not transititve

jolly jasper
#

huh?

#

then is it transitive?

tight pier
#

yes

jolly jasper
#

how?

tight pier
#

Consider two cases first (a,a) where a in A

#

aRa and aRa implies itself trivially

#

the other case is with the (1,2)

jolly jasper
#

that's aRb, correct?

tight pier
#

1R2 and 2R2 implies 1R2

tight pier
#

and the only match bRc is for example (2,2)

#

on that set

#

How about 1R1 and 1R2 ?

jolly jasper
#

quick question. how is (2,2) bRc?

#

aren't we supposed to take each element in set A as a, b and c?

tight pier
#

b=2 and c=2

#

a,b and c can be the same

tight pier
#

i consider the case a=b=c

#

aRa and aRa => aRa is the same as aRb and bRc => aRc if a=b=c

jolly jasper
#

Wait so we don't assign each element in set A as a, b and c? like a=1, b=2 and c=3. so (1,1) is aRa, (1,2) is aRb and if we assume there's (1,3) then that would be aRc, no?

tight pier
#

nooo

jolly jasper
#

???

tight pier
#

a,b and c are not to be chosen constant

#

they are arbitrary

jolly jasper
#

I see.

#

Then how are we assigning those respective values?

tight pier
#

what you are doing is you are finding matching pairs

#

you can have (1,1) and (1,2) then a=b=1 and c=2
you can also have (3,3) and (3,3) then a=b=c=3 now

jolly jasper
#

Ohhhhh.... I see now.

tight pier
#

a,b and c are just place holders

jolly jasper
#

Wait. Let me try to find how this is transitive on my own if i still don't get it I'll ask for help. brb in 5 minutes.

#

TY.

#

Hello?

median oar
#

well you haven't said anything...

jolly jasper
#

is this correct? if i take (1,1) as aRb, (1,2) as bRc and (2,2) as aRc? so its transitive?

tight pier
#

well it's an example but not proof

median oar
#

transitivity is a for all statement

#

you need to show it's true for every aRb and bRc that it means aRc

#

not just 1 pair

jolly jasper
#

ohhh i see.

#

so (1,1), (1,1), (1,1) and (1,1), (1,2), (1,2) as aRb, bRc and aRc respectively?

median oar
#

there are some other ones

#

namely 2 more really trivial looking ones

#

looks like the (1,1), (1,1), (1,1) one

jolly jasper
#

(3.3) and (2,2)?

median oar
#

yeah

#

that's all the ones you can pick of the 4 that have the form aRb and bRc

#

oh there's also (1, 2) and (2, 2)

#

so 3 more you were missing

jolly jasper
#

so another quick question. so if R has (x,x) does that mean it's automatically transitive?

median oar
#

what does (x,x) mean

jolly jasper
#

any element.

#

i thought of putting "a" but decided not to.

#

like (3,3), (2,2) , (1,1) and so on.

#

Sorry my english is not so good :(

median oar
#

all of them

#

if all of them are in there it probably is a yes

jolly jasper
#

Okay. That will be all. TYSM.

#

.close

lone heartBOT
#
Channel closed

Closed by @jolly jasper

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#
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After 15 minutes, feel free to ping <@&286206848099549185>.
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faint spindle
#

Hello, how do I factorise further?

lone heartBOT
pale kestrel
#

i would not keep that x(y+1) inside there

#

What is the overall goal?

faint spindle
#

To factorise it to 3 brackets

pale kestrel
#

if ur asked to factorise that entire expression, then u probably need to multiply it out first

crisp turtle
#

ok u need to resolve the - xy to do that

#

so u need to multiply it all out, expand it all out first

#

then factorize

faint spindle
#

Can I have step by step help perchance

crisp turtle
#

first step
multiply it all out

faint spindle
#

Like how?

#

I'm sorry I'm really stuck at it😭

lone heartBOT
#

@faint spindle Has your question been resolved?

faint spindle
#

<@&286206848099549185>

pale kestrel
#

have you been shown how?

slim kite
pale kestrel
#

(a+b)(c+d) can you expand this?

faint spindle
#

Nah nvm I think I found out

#

How do I close the question

slim kite
#

Type .close, but...

#

I'm curious

faint spindle
slim kite
#

Can u share the solution

faint spindle
#

. rotate

#

Oh wait

#

. close

#

.close

lone heartBOT
#
Channel closed

Closed by @faint spindle

Use .reopen if this was a mistake.

pale kestrel
#

,rotate270

ocean sealBOT
slim kite
lone heartBOT
#
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heavy prairie
#

Solve the equation:

lone heartBOT
heavy prairie
#

sending pic of what i tried

#

i thought i would have to divide into cases but apparently i can eliminate one of the two answers for cosx

#

but i dont understand why or how i can eliminate one

#

is it something about false roots?

#

i never understood false roots that well

civic cedar
#

try equation cosx with y in step 3 and then try solving. i think one of your roots is incorrect

heavy prairie
#

what y

civic cedar
#

any variable

#

the roots i got were 1/2, -2

heavy prairie
#

oh yeah whoops

civic cedar
#

and then it is easier to eliminate one of these roots

heavy prairie
#

my negative root should be -2 not -1/2

civic cedar
#

yup

#

so -2 is eliminated as cos x = -2 is not valid

heavy prairie
#

am i supposed to use that -1 <= cosx <= 1?

civic cedar
#

yes

heavy prairie
#

ok

#

i will try to continue from there

civic cedar
#

cool

heavy prairie
#

okay i still need help

#

i know that for cosx to equal 1/2, x would have to be +-pi/3 + 2pik, where k is an integer

#

do i just have to test what ends up equaling 0 in the original problem?

pale kestrel
#

goal is to write general form of solution

#

which is what ur doing

heavy prairie
#

but would that be true even for sin^2?

pale kestrel
#

using pythagoras is an iff

#

quadratic formula is also an iff

heavy prairie
#

im not sure what iff means

pale kestrel
#

sin^2 x - 3/2 cos x = 0
1 - cos^2 x - 3/2 cos x = 0

#

x is a solution for the 1st if and only if it is a solution for the 2nd

#

youve substituted in an identity that is true for all x

#

similarly, when you apply the quadratic formula to get cos x = +-1/2 (ill assume ur math is right), its the same story

heavy prairie
#

^ ah yeah it was wrong but the other person caught it

pale kestrel
#

If cos x = 1/2 or cos x = -1/2, then x solves your other equation too

heavy prairie
#

the negative root was cosx = -2

pale kestrel
#

ok, whatever it is but yeah

heavy prairie
#

i turned -8/4 into -2

#

but that eliminates that root

#

i guess i dont understand how one thing implies the next

#

the identity i used is called "trig-ettan" in my language

#

with sin^2 + cos^2 = 1

#

and i just rearranged it

#

to get a quadratic where i could solve for cosx

#

so i guess that far i follow

#

i didnt change anything

pale kestrel
#

yes theres no reason this process loses you or gets you extra solutions

heavy prairie
#

and it is still the same equation as the original

pale kestrel
#

you can draw this on desmos if youre not convinced

#

draw every new equation you get

heavy prairie
#

but then i lost a root because it isnt defined

pale kestrel
#

oh

heavy prairie
#

or is it called something else

#

than undefined

pale kestrel
#

cos x = 1/2 or cos x = -2

heavy prairie
#

sinx = 3 for example

#

what do i call that

pale kestrel
#

well yeah

#

no real solutions

heavy prairie
#

undefined or not possible?

#

oh ok

pale kestrel
#

latter

#

anyways

#

if uve done elementary logic at all

#

you would know that given x is real,
cos x = 1/2 or cos x = -2
if and only if
cos x = 1/2

#

iff is if and only if

#

the double implies sign

#

<=>

heavy prairie
#

ah ok i know about the equivelant sign but

#

i didnt know iff meant if and only if

#

my native language isnt english

pale kestrel
#

If your working goes from the start to the end using <=>, then you dont need to worry about losing solutions

#

or having extra

heavy prairie
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when going from

pale kestrel
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yes thats not strong enough

heavy prairie
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okay so i can put an equivelant arrow there

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then i see that i wouldnt be losing any solutions or getting extra

pale kestrel
heavy prairie
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ok thanks

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both of you

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.close

lone heartBOT
#
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ebon anchor
#

hello, I’m stuck on this problem.

I assumed that v1, v2, v3, p1, p2, p3, are all 0-forms, since they have no differential in them, but then I feel like every part of this question would have the answer of “0-form”, so I think I’m missing / misunderstanding something about p-forms, but I’m not sure what.

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kind glade
rustic coral
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<@&268886789983436800> ^

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#
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#
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Remember:
Ask your math question in a clear, concise manner.
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coral rune
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How do i do this because I keep coming up with undefined as my answer

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coral rune
#

just rewriting in a more readable way sorry gimmie a sec

coral rune
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violet jetty
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if I had to guess... you're getting undefined because you're trying to evaluate sin(x)/x at x=0, which is 0/0

coral rune
coral rune
violet jetty
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In that case you should just use the limit at that point no?

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Because you're ultiamtely trying to evaluate the "height" of the function to get your average for Simpson's rule

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since the true value does not exist at x=0 (undefined), you can still figure it out if the discontinuity is a removable one (ie. a hole)