Mathematics - 2014-06-09 (page 3 of 3)

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10:01 PM

Not much chatty chat going on huh

nope ... we're antisocial

Sigh

No meat, no pudding.

whatever that means

I am not sure myself, lol.

10:03 PM

ok, I'm outta here

Well you often classify it as introverted or antisocial. Whereas the first has a medical term, attatched to it.

The other one was used previously but now is just slang for cool kids..

What's the difference between asocial and antisocial

Read up on asocial personality disorder and antisocial personality disorder.

In everyday language, the words have different meanings.

So check the dictionary for asocial and antisocial.

public.wsu.edu/~brians/errors/asocial.html

nobody uses asocial in everyday language

10:07 PM

Never heard antisocial being thrown around much either, then again I am not a native.

I still have no idea why I was flagged yesterday @MikeMiller

How do you undo a flag

You can't undo it

I wanted to suprise a dear friend of mine by waking her up with breakfast, coffee and the newest episode of a tv-series she fancied. I walked about half an hour to her house, early in the morning only to find out she had spent the night elsewhere. fml =)

You broke into her house?

10:12 PM

@N3buchadnezzar Sounds like you want her as a gf.

@nablablah $\exists ! \ Roomate \geq 0 \ ; \ Roomate \ \in \ \mathbb{N}$

Not necessarily

I would do that for you @JasperLoy

@nablablah Aww.

@N3buchadnezzar Are you still single?

y

Being nice shugs

@Chris'ssis have you seen this 'baby' ? $$\lim\limits_{n \to \infty} \dfrac{(-1)^nn^2}{n!} \sum\limits_{k=2}^{n}\binom{n}{k}(-1)^kk^{n-1}\ln k$$ ? :D

10:16 PM

@r9m yeah, you showed me this in the past and said it equals a multiple integral :D I also have it in some paper if I'm not wrong.

@Chris'ssis I'm thinking of asking it on the main ... but if someone asks to show my work I'm fried :P (ya the result is due to Furdui Ovidiu :P lol .. not me :P)

@r9m :)))

I'll be the first to demand work shown

You can have my "what have you tried" and my "is this homework?" too!

Hi folks!

10:17 PM

So lets destroy the abelian rings in mount doom >.<

As a group >.<

@r9m that guy is a real genius

@Chris'ssis true :)))

does any one know any golden trick on how to memorize some of usuel series expansion

No trick, just memorise, lol.

@pourjour Amphetamines.

10:19 PM

@PedroTamaroff do you use them ? :)

lhf seems to have vanished completely

@r9m No, I do caffeine.

@PedroTamaroff I usually take Vitamin C

Make a new account "Jasper lhf" which asks low hanging fruits, then you answer them! Nobody will expect a thing

@r9m btw, I'm very glad for computing that series I showed you. It's probably one of my greatest achievements this year.

10:22 PM

@Chris'ssis But your paper should begin with "Solution to the epic series that I created on ...."

@r9m lol :-)))))))) You have no idea how nice I feel because of that. I feel myself so fulfilled! :-)

@PedroTamaroff I do antidepressants, lol.

@Chris'ssis Which is why you should publish your book one day.

@JasperLoy Yeah, I have to. I'm full of ideas every day, but not some, maybe hundreds of them ...

@Chris'ssis Throw yourself a party or pop a beer :D !! relax for a while :P (but I doubt you can stay away from more creative stuff for long .. you are possibly swarming with ideas right now :P lol)

@JasperLoy Have you found out why you're depressed?7

10:25 PM

@r9m loooooollllllllllllllllllll You got me with the last words ... :-) (I was just thinking of some stuff)

@PedroTamaroff Well, antidepressants are used not only to treat depression but also things like OCD. But anyway, people with OCD often have depression as well, because OCD causes so many problems.

Has anyone here watched Anastasia or Elfen Lied?

Yes

I saw Anastasia in the movie theatres

@N3buchadnezzar Anastasia is that cartoon?

@Chris'ssis you always do that -_- ... tell me smthng that I don't know :P .. I know you think .. what I don't know is what you think :P

10:28 PM

@PedroTamaroff Disney yes

I am thinking of watching nice movie series. What should I watch?

I don't think Anastasia is Disney

@JasperLoy Can you watch one without reading about it beforehand?

@N3buchadnezzar Yes, if you tell me it is worth watching.

Anastasia is a 1997 American animated musical fantasy drama film produced by Fox Animation Studios and distributed by 20th Century Fox

@JasperLoy It is one of the best I've ever seen

10:29 PM

@N3buchadnezzar For animations, I like The Polar Express!

@r9m :D

I liked the Polar Express book

@nablablah What did you think of it?

@N3buchadnezzar The Polar Express?

@JasperLoy "Now and Then, Here and There" or "Ima, Soko ni Iru Boku" in japanese, got a 8.2 rating on IMDB.

@nablablah Anastasia

10:31 PM

@N3buchadnezzar Soko ni Iru is too depressing

@nablablah Please remove

Its spoilers =/

@N3buchadnezzar Ok

@r9m have you seen this one? $$\lim_{n\to\infty} \frac{\displaystyle \int _{1/2}^{1} \operatorname{Li}_2(x)^{n+2014} dx}{\displaystyle \int _{1/2}^{1} \operatorname {Li}_2(x)^{n} dx}=\zeta(2)^{2014}$$

I like watching, and reading things without knowing anything about it.

Not even genre, makes me watch it without any prejudices or expectations.

The comment above >.<

@Chris'ssis ya .. is it very difficult ? :-)

10:33 PM

@nablablah So you did not like it because of the genre?

@r9m No. It's easy-medium. (very easy if you look at it in a certain way)

I mean Grave of the Fireflies is great...

@N3buchadnezzar I didn't like it because of the emotions it evoked

@N3buchadnezzar you have just remind me of a girl "Anatasia ukraine got talent" you can watch that video at youtube

But is not movies, tv-series about feeling different emotions?

10:34 PM

@N3buchadnezzar Just brought up bad memories from my personal life

Same

Totoro <3

@N3buchadnezzar It triggered self-harming

So I can't watch things like that

@Chris'ssis okay .. I'll try it :) .. however it has the $\dfrac{\int f^{n+k}}{\int f^n}$ form .. which is nice :D

@r9m Indeed! :-)

@nablablah Iron Giant or Mulan is nice :p

10:36 PM

@N3buchadnezzar I find those boring

Well iron giant was real sweet and mulan had interesting music and a female protagonist. Zomg, gender bender

@N3buchadnezzar Iron giant is wonderful

Yeah I want to find someone to share these with

Howls moving castle is nice, and that bunch

Even though I am starting to grow tired of Sprited Away, must been my tenth of fifteenth time seeing it.

My favourite must be Nausicäa, Valley of the winds. Gets me everytiem

I think they are purposely not posting lhf on main, lol.

I posted a couple lhf today @JasperLoy

Sorry

10:41 PM

@JasperLoy go watch "Here and there, now and then"

@nablablah Have I told you my nine holy books?

@N3buchadnezzar Is it in English?

@JasperLoy Once, but I forgot them

@JasperLoy Yes, but I preffer japanese with english subtitles.

@N3buchadnezzar My favourite Japanese drama series are Heaven's Coins 1 and 2.

@JasperLoy How come you don't like Dummit & Foote

10:46 PM

@r9m did you find a way for this one?

@nablablah I prefer algebra books where rings are defined with 1.

@JasperLoy Why does it make such a big difference

$$\lim_{n\to\infty} \int_0^{\pi/2} \frac{1}{ \displaystyle \cos^2 \left( \frac{x}{2} \right)\left( \cos^2\left( \frac{x}{2}\right)-\cos^2 \left(\frac{x}{2^2} \right)\right)\cdots \left(\cos^2\left( \frac{x}{2}\right)-\cos^2\left(\frac{x}{ 2^{2n+1}}\right)\right)}+ \cdots +$$

$$\frac{1}{ \displaystyle \cos^2\left( \frac{x}{ 2^{2n+1}} \right)\left(\cos^2\left( \frac{x}{ 2^{2n+1}}\right)-\cos^2 \left( \frac{x}{2} \right) \right)\cdots \left( \cos^2\left( \frac{x}{2^{2n+1}} \right)- \cos^2 \left(\frac{x}{2^{2n}} \right)\right)} \ dx=\pi \log(2)$$

@nablablah It becomes very irritating when more than half the results are stated as "ring with 1" instead of just "ring".

@Chris'ssis I haven't tried that yet ..

10:47 PM

@JasperLoy I'm sorry

@r9m Ah, OK. I thought you tried that.

@Chris'ssis lol reaks of the logarithmic derivative of a telescoping telescoping product

@JasperLoy Just watch it, then discuss/talk afterwards

@Ethan :-))) I think it's very cute.

im guessing? am I write

10:50 PM

@ethan Will you be starting work soon?

@JasperLoy yeah

@Ethan Let me read through your essays next year before you submit them.

i will

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@Ethan I was reading, what the hell Ethan.

oh

10:54 PM

lol

LOL

$$f_a(x)=\sum_{n=-\infty}^\infty\frac{a^n}{x^{a^n}+1}$$

$$af_a(x^a)=f_a(x)$$

$$f_2(x)=\frac{1}{\ln(x)}$$

$f_a{

$$f_{2^{1/j}}(x)=\frac{j}{\ln(x)}$$

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

$$\sum_{n=-\infty}^\infty\frac{(\sqrt{2})^n}{(\sqrt{2})^{(\sqrt{2})^n}+1}=\frac{‌4}{\ln(2)}$$

$$f_{a^n}(x)+af_{a^n}(x^a)+a^2f_{a^n}(x^{a^2})+\dots +a^{n-1}f_{a^n}(x^{a^{n-1}})=\sum_{k=0}^{n-1}a^kf_{a^n}(x^{a^k})=f_a(x)$$

$$f_4(x)+2f_4(x^2)=\frac{1}{\ln(x)}$$

$$\phi+1=\phi^2$$

What are you trying to do with all that @Ethan?

11:00 PM

$$\sum_{n=-\infty}^\infty \frac{4^n}{(\phi)^{4^n}+1}+2\sum_{n=-\infty}^\infty\frac{4^{n}}{(\phi+1)^{4^n}+1‌}=\frac{1}{\ln(\phi)}$$

who knows, thats what makes it fun

Are you studying from Apostol?

havn't had time I'm like half done with his introduction to number theory

analytic number theory* will probably have to go back and read rudin

Cool, just keep going. =)

@Ethan Rudin/Spivak are great. Rudin is a bit harsher.

Not harder.

Just harsher with the reader.

i kno of his book on manifolds and another 1 on calculus, spivak, havn't read either though

isn't he the guy who does that thing with pig refrences

yellow pigs

Yes.

He's good.

11:02 PM

haha

@Ethan what do we have below?

?

haha lol i posted it a long time ago

Oh, look, telescopy! Who would have guessed that!?

@Ethan Link?

i was just reviewing old lines of latex in .txt files on my comp

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@Ethan $\log(1+1/2)$?

11:08 PM

$$\ln(3/2)$$

No shit =D

lol

nvm thats a bad one

I need some sleep now. @Ethan let me know if you find a way for the limit above (it's pretty straightforward).

i wasn't working on it

I assume you took the logarithmic derivative of some infinite telescoping trigonometric product

@Ethan No ...

11:12 PM

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No ...

@Ethan Damn son, that answer is bananas.

Out for some sleep

Hi

is there anyone here that is good in combinatorics ?

@gbox I know some.

=)

11:15 PM

@PedroTamaroff if I need to find the number of solution to the following $4x_1+3x_2+2x_3+2x_4=9$:

@gbox $x_i$ integers, nonnegative, positive...?

solutions over what

yeah

@PedroTamaroff yes

"yes"

its not a yes or no question lol

11:17 PM

sorry :(

he means

over what range of values do the values $x_1,x_2,x_3,x_4$ take on

are they supposed to be integers only?

integers and nonnegative

well you can already tell some have to be zero, because when they are each one you get something over $9$

sure like the 4x

alright well 9 is odd

and any multiple of $2$ or $4$ will be even

11:19 PM

@gbox You can use generating functions.

here reduce both sides modulo 2

$$4x_1+3x_2+2x_3+2x_4\equiv 9 \text{ mod 2}$$

$$x_2\equiv 1 \text{ mod 2}$$

I think it is too complicated

nah

maybe I will tell you all the question

thus $x_2$ must always be one of the following $1,3,5,\cdots$

you just need to find all the solutions now to uhm

no wait I got it

one solution is $(x_1,x_2,x_3,x_4)=(0,3,0,0)$

11:22 PM

ok

all other solutions are solutions to $$2x_1+x_3+x_4=3$$

with $x_2=1$

take a look for a sec

@gbox You want $x_i\geqslant 0$?

need to divide 20K of money to 4 programs of 4K, 3K,2k,2K and must put the money in all the 4

@PedroTamaroff yes

Come again?

Oh, OK.

11:26 PM

alright so now we know reducing both sides modulo $2$ that $x_3+x_4\equiv 1 \text{ mod 2}$

so we have

$$2x_1+0+1=3$$

$$2x_1+1+0=3$$

$$2x_1+3+0=3$$

$$2x_1+0+3=3$$

$$2x_1+2+1=3$$

$$2x_1+1+2=3$$

@PedroTamaroff I got to 9 because I said, ok lets invest in each one (sums to 11 so it is 20-11)

@Chris'ssis I can't help but thinking I've done something similar, but I can't find it at the moment.

there should be 7 then

and the answer is 220

ELU is having a mod election, will MSE have one too @robjohn

11:28 PM

@gbox Err, I think something is off. You want $20=4x_1+3x_2+2x_3+2x_4$

I'll vote for you @Jas

If you investments are not to be $0$, then $x_i>0$.

@PedroTamaroff yes x>0

@JasperLoy I don't think so. Unless there are some untimely accidents, I think we have enough to handle the load.

Why did you put $=9$ then...?

Oh.

OK.

You're right.

What you can do is solve $20-4-3-2-2=9=4x_1+3x_2+2x_3+2x_4$ with $x_i\geqslant 0$.

This is not hard since $9$ is pretty small.

11:31 PM

@PedroTamaroff yes but the answer in the book is 220

that is just like it was $x_1+x_2+x_3+x_4=20$

No, that is not what the book is asking.

I know

If $x_1=0$, you're solving $9=3x_2+2x_3+2x_4$.

For $x_2=0$ there are no solutions since RHS is even.

So $x_2\neq 0$.

@PedroTamaroff the only way to do so is to check one by one?

No, there are other options.

But it looks sensible to do so in this case.

11:34 PM

I agree

but what if it was a bigger number

@nablablah What will your next username be?

lets say not 20

You could use generating functions.

@PedroTamaroff way above my knowalge

Knowledge.

11:37 PM

yes sorry it is 2am here

ok @PedroTamaroff and @Ethan thanks a lot you are great

and the site it, too

There's a time of the day you decide to f**k up your spelling? ;)

@PedroTamaroff lol

btw I am the bot that passed turing test

lol :)

WAT.

all the media talks about it

"A computer just passed the Turing Test in landmark trial'

calling it a day

thanks

buzzfeed.com/kellyoakes/…

11:50 PM

@JasperLoy I'll just keep this for the mean time

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