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r9m
2:01 PM
$ (|x-y|+|y-z|+|z-x|)^2 \ge ((x-y) - (y-z) +(x-z))^2 = 4(x-y)^2$
 
@robjohn Niw I proposed to myself (but not for now) these ones $$\lim_{n\to\infty} \int_0^1 \int_0^1 \cdots \int_0^1 \cos\left(\frac{n }{\displaystyle \frac{1}{x_1}+\frac{1}{x_2}+\cdots + \frac{1}{x_n}}\right) \ dx_1 \ dx_2 \cdots dx_n$$

$$\lim_{n\to\infty} \int_0^1 \int_0^1 \cdots \int_0^1 \cosh\left(\frac{n }{\displaystyle \frac{1}{x_1}+\frac{1}{x_2}+\cdots + \frac{1}{x_n}}\right) \ dx_1 \ dx_2 \cdots dx_n$$
@robjohn then I wanna attend to root mean square version as integrand in the multiple integral limit.
@robjohn I'm really curious about that version (RMS).
OK, that's all for now. I'm out.
 
@hawk Was I right or not?
 
What is the point of Harry potters [sic] answers on the site?
 
wat @N3buchadnezzar
 
I mean they never give a value for their answer only "hints" or absurd sums
 
2:15 PM
Who is it though?
i can't find the user
 
@N3buchadnezzar I found three Harry Potters, with one answer between them. That was a link, not a hint.
 
Notice the sic part? I misspelled the name on purpose..
 
that seems silly.
 
See this for an example
 
ahahaha that hint
 
2:19 PM
every single "answer" he has is of that form, or worse
Grinds me gears
 
r9m
@Sawarnik So .. what do we do after that ?
 
Say we prove that $\Gamma(s)$ is analytic for $\sigma>0$, where $s = i t + \sigma$. Does this prove that $\Gamma(s)$ converges for all $\sigma>0$?
 
well, an analytic function is a function...
so if $\Gamma(s)$ is analytic on a domain, then by definition it's defined on that domain :p
 
2:34 PM
@Mike Btw why are we so interested in uniform convergence?
 
ahahahaha that was idiotic.
now i maintain it wasn't my fault, because he should have written "imaginary part" >:(
 
r9m
@Sawarnik AHA .. more than half the credit should go to my roomie .. we did it together :) :D (infact proved a far stronger result)
(will write it after I come from dinner)
 
2:55 PM
@r9m Aha! Wow.
Your roomie is a master of inequalities it seems.
Come fast!
 
3:15 PM
@r9m Where are you ... I m waiting!
@ParthKohli Hi -_-
 
3:31 PM
@Mike Mike here?
I was just wondering if anyone had any other sources for lemma 2 and 3 from this document.
 
@Sawarnik Heya.
 
@BalarkaSen Hi.
 
@BalarkaSen Hello.
 
@BalarkaSen Yo
 
Oof, quite a warm welcome.
 
3:40 PM
:)
 
Anything for you, your highness!
 
@all Hellos.
 
I think there is no user all.
 
'@' mean "to"
So no user involved in pinging.
 
its spelled "y'all" dawg
 
3:41 PM
Is there any reason why humans becomes so intelligent while other animals did not? And why did we became intelligent in the first place?
 
@Sawarnik 9th Biology Diversity in Living Organisms
 
@Sawarnik We never know.
The other animals might be intelligent.
 
@BalarkaSen No, of course not.
@ParthKohli Does it give any reason why humans became intelligent?
 
TL;DR: as organisms evolve, they become more complex. We're the latest in evolution, and also the complex.
 
@Sawarnik Ah, proof?
 
3:43 PM
"Complexity" in biology is generally progress.
 
@ParthKohli Many animal species are recent, but they are not as intelligent.
 
@Sawarnik They are not a result of so many periods of evolution.
 
@ParthKohli I think so, what is the reason then exactly?
 
Define "intelligent". It's all relative.
 
@Sawarnik Some organisms evolve; some do not...by natural selection. You should Google evolution.
 
3:45 PM
Oh, by the way, have anyone tried my transformation exercise?
 
@ParthKohli So this is q: what factors led us to become intellegent?
 
$x^3 + ax + b \mapsto x^3 + ax^2 + b$
 
@Sawarnik E, V, O, L, U, T, I, O, N.
 
@ParthKohli OK. But evolution happens due to some reasons. Not random.
 
A stone is intelligent too, but to a lesser degree.
 
3:46 PM
@MatsGranvik Exactly.
2 mins ago, by Balarka Sen
Define "intelligent". It's all relative.
 
@Sawarnik That's what you should Google. We're the result of evolution.
 
@MatsGranvik No, a stone is not. A worm is.
@ParthKohli I KNOW. But did evolution made us intelligent, while other animals did not?
 
It's called natural selection.
 
@Sawarnik A worm is more intelligent than a stone, I agree.
 
I don't know the details.
 
3:47 PM
@ParthKohli You are telling its all evolution. Of course it is, but my q is more specific.
 
@Sawarnik Other animals have not evolved as much as we have.
 
Actually, dolphins. And mice.
 
Cats.
 
@ParthKohli What do you mean?
@DanielFischer Nowhere like us.
 
You should actually read that chapter in your textbook.
Just read it.
 
3:48 PM
@Sawarnik Relative.
They might just be.
 
@Sawarnik You didn't read the Hitchhiker's Guide, I take it?
 
Balarka, if we take human beings to be zero on the relative scale, then there's no doubt that all other known organisms will be negative.
 
@ParthKohli What do you mean exactly "Other animals have not evolved as much as we have"? Tell.
 
@Daniel I appreciated your comment, at least.
 
@ParthKohli Yup.
 
3:49 PM
@ParthKohli Relative.
Cats might show different kind of intelligence totally unknown to us.
You never know.
 
Yes, dogs know when an earthquake is coming!
 
Precisely!
 
Dogs have traits that we don't.
 
But that does not mean they are as intelligent as us.
 
But I hold the argument that we're the most intelligent.
 
3:50 PM
@ParthKohli That doesn't mean they are less intelligent.
 
@ParthKohli You didn't tell what did you meant by that?
 
I've been making a lot of stupid mistakes this morning...
 
@Sawarnik I can use the same argument.
 
@Sawarnik Please, please, please read that chapter. Please.
 
@ParthKohli I know enough about evolution, then what I think would be in that chap.
 
3:52 PM
@Mike Like editing that statement?
 
So tell what you mean by that?
@BalarkaSen Dogs don't have language or writing for example.
 
@Sawarnik That doesn't mean they have lesser intelligence or no way of communication.
I am not sure about the language.
 
@BalarkaSen What do you mean by intelligence?
 
Have there been any study on this, or do we just hypothesize?
@Sawarnik I asked the same question to you.
10 mins ago, by Balarka Sen
Define "intelligent". It's all relative.
 
The cognitive ability to memorize, think ..... that will lead the organism to a better life. Is it good?
 
3:56 PM
How do you know that they don't think?
 
@BalarkaSen They think of course, but not to our extents.
 
How do you know that?
They might think in a different extent not comparable to the way we think.
It might be almost the same as comparing $1 \in \Bbb R$ with $a \in V_4$
 
So what is the use of their sixth sense thinking?
Would be there an purpose?
 
@Sawarnik Maybe, maybe not.
My point is, we don't know.
 
@BalarkaSen No, they would have an advanced lifestyle then. And may have lived in houses , and ...
But its not.
 
3:59 PM
@Sawarnik You cannot prove that implication.
 
Oh spare me! I m not a logician.
 
That's your problem, Daniel San. =D
 
@ParthKohli Did you mean that humans are the most recent animals?
 
I am going to pull myself out of this discussion.
 
@Sawarnik No, I don't.
 
4:03 PM
Byedy Byes!
 
@BalarkaSen Byes! :)
 
But they've evolved for the most years.
I mean they're the most complex result of evolution.
 
@ParthKohli So why us? Why not the other animals which have been evolving in the same time?
@ParthKohli That's the most ambiguous line I have seen.
 
@Sawarnik You should ask someone else.
 
Anyways, you are not ignoring me! Yay!
 
4:06 PM
But Homo sapiens are stated as the last species, IIRC.
 
well that's obnoxious looking
 
@ParthKohli What do you mean by last species?
 
yikes, the infamous three all in one room
 
Oh, the 14-club!
 
@Sawarnik Oh God, just read the chapter, will you?
@meer2kat Haha.
 
4:07 PM
@ParthKohli No, I haven't come across the term last species. Can you tell me what does that mean?
 
@Sawarnik You state the species in order of evolution.
I'll just go to general.
 
r9m
@Sawarnik if you are really interested .. then break the problem into showing $\sum_{cyc}\left(\dfrac{x^2}{y}+y\right) \ge 6\dfrac{x^2+y^2+z^2}{x+y+z}$ and the trivial $6\dfrac{x^2+y^2+z^2}{x+y+z} - \sum_{cyc}x > 4+(x-y)^2$
 
@r9m :| When will you post the solution anyways?
 
@Sawarnik youngins
 
@meer2kat Is that a portmanteau of young and Indians?
 
r9m
4:11 PM
@Sawarnik maybe .. Never (people should care about such ugly mathematics) .. and more over the solution is highly inaccessible to you .. so you could care less :P (I can post it here if you want .. but I'm not doing it on main)
 
@ParthKohli ....no
 
@r9m Oh. But you should post to tell that its been solved.
Coming in 10 mins...
 
it just means "young person"
i'd say it's more of a portmanteau of young and ones
 
@r9m And people could know your general form....
 
@meer2kat Young + Indians would just work as well. Bonus: if you say the word "Indian", you need not mention the implied "infamous." :)
 
4:18 PM
@ParthKohli oh one of the wild kids is in a cheerful mood today. perhaps it is a trap!
@ParthKohli yes it would work. but some would take offense and that is not what the word, in fact, means.
@robjohn Can mods see who stars what and who flags what? I'm purely curious
 
@N3buchadnezzar -umbug
 
@meer2kat I'm secretly a moderator. Your answer is yes.
 
I can not find a single proof for holders inequality in any of my books. I hate citing :p
 
@ParthKohli shrugs i'll believe you
@N3buchadnezzar site wikipedia. teachers love that
 
4:21 PM
@meer2kat You'll have to believe me. Otherwise, I'll ban you with my cruel intentions.
 
@meer2kat Who cares about teachers.. I am not writing for them..
 
@ParthKohli fair enough.
 
@meer2kat Comm team members (super-mods) can probably see who stars what, but not us mere site mods. As for flags, I think with some recent changes to the site, we can see who has flagged a given post. I know we can see who has made a custom flag (the kind where you fill in the blank).
 
@N3buchadnezzar oh watcha doin then?
 
@meer2kat Document
 
4:23 PM
@robjohn You forgot to mention that secretly hired moderators (such as myself) can. ;-)
 
@robjohn fancy schmancy; I was curious due to the PSA in the star queue
@N3buchadnezzar .doc
 
@ParthKohli need I test that hypothesis by trying to boot you? ;-)
 
@meer2kat pdf
 
@robjohn Screw you and your awesomeness! :)
 
@N3buchadnezzar .txt
 
4:24 PM
@meer2kat I hate receiving an attached .doc. PDF is a far more portable format.
 
@robjohn Agreed
 
hi
 
hola
 
Is there a difference between A%B and A mod B
 
@robjohn Especially with LaTeX.
 
4:25 PM
?
and mod(A,b)
 
@meer2kat -woo, I found a proof in my book!
Lazy Rudin never names his equations
 
@N3buchadnezzar woowoo confetti
 
@Sohaib usually, A%B has the same sign as A and A mod B has the same sign as B, but it depends on the implementation
 
@robjohn Okay. Also is mod(A,1) always 0?
 
@Sohaib if A is an integer, yes
 
4:29 PM
@robjohn I saw this in a research paper. Doesnt seem to make sense 0.o
 
@Sohaib otherwise, it will be a real in [0,1)
 
@robjohn Oi! Now it makes sense!! Thanks a lot!
 
@Sohaib cool!
 
4:43 PM
@meer2kat Hi.
 
@Sawarnik hey kid
@Sawarnik you can send em at me if you want lol
 
I should probably do useless chatting.
Hey PK.
 
@Sawarnik a < b
but b > c
and d= 12. why????
 
You knows.
 
it's quite simple
i said so. that's why.
 
4:54 PM
@meer2kat Its time I change my profile pic on FB. What could I put?
 
@Sawarnik a picture of you?
 
@meer2kat i hardly have any other picture of me on this computer :(
 
@Sawarnik take one then so the world can know what you look like :)
 
@meer2kat Well, the current one is my picture only!
 
@Sawarnik huh?
 
4:57 PM
@meer2kat On FB.
@meer2kat Wasn't it a nice pic?
 
yep
i forget how young you are
 
@meer2kat Actually that was me of I think about 9 years.
I love that pic, plus the rural background, looks perfect.
 
@DanielFischer When you wrote "a while" did you have in mind a time $t$ greater or less equal to 9 minutes?
 
@Sawarnik :)
 
:15094380 he talked at a couple of meetings, but I never met him in person.
 
5:09 PM
@robjohn Ok :)
 
@MattN. Half an hour at least. In nine minutes, one can barely fetch the paper.
 
loool @robjohn I found a solution to a question that Euler and Ramanujan together would cry seeing! :-))))))
(it's for the version of arithmetic mean as integrand in a multiple integral)
 
n11
5:25 PM
$\sum\limits_k{\sum\limits_i{\sum\limits_j z_i \phi_k^i \phi_k^j z_j}} = \sum\limits_k{(\sum\limits_i z_i \phi_k^i)^2}$ is it obvious? (superscript is just an index)
 
r9m
@Chris'ssis which question ?
 
Quick question for anyone, is the ratio test passing when the real part is less than one, or when the magnitude of the limit is less than one?
 
Magnitude, @MickLH.
 
'phew lol
thank you very much
 
n11
(i and j are in the same ranges of course)
 
5:32 PM
@Chris'ssis not the harmonic mean, as in the last problem?
 
@robjohn not the harmonic mean, but the arithmetic mean instead. @robjohn, it's simply mind-blowing!
 
@Chris'ssis so which problem is this?
 
5
A: How prove this integral limit $=f(\frac{1}{2})$

r9mStarting with OP's hint, $\displaystyle \lim\limits_{n\to\infty}\int_{0}^{1}\cdots\int_{0}^{1} \left(\dfrac{x_{1}+x_{2}+\cdots+x_{n}}{n}\right)dx_{1}dx_{2}\cdots dx_{n}=\dfrac{1}{2}$, Now, we try to show, $\displaystyle \lim\limits_{n\to\infty}\int_{0}^{1}\cdots\int_{0}^{1} \left(\dfrac{x_{1}+...

 
@Chris'ssis Ah, I'd not seen that one yet.
 
@r9m you posted yesterday a question with multiple integral where you had some log in integrand. Does it have a closed form? Are you aware of such a form?
 
r9m
5:40 PM
@Chris'ssis none yet .. although $1/log$ is not continuous in [0,1], I'd vote for $1/log(1/2)$ ..
 
@r9m For that reason I refrained myself from considering it $1/\log(1/2)$.
 
@Chris'ssis That is simply the Central Limit Theorem.
 
@robjohn Indeed. :-)
I'll be back a bit later.
 
Hey guys thanks for the quick response, I've gotta conserve mobile data though so I'll be around later
 
r9m
@robjohn I didn't understand the proof with random variables .. it seemed to me that it solved the problem like some kind of butter flow .. where should I start reading ?
 
5:46 PM
@r9m let me take a look at the answers...
 
6:21 PM
like butta!
 
6:59 PM
@robjohn math is definitely more beutyfull than poetry. It took a lot more work too
 
@DanielFischer I thought you might say that : )
 
7:27 PM
Let me post now a very beautiful limit $$ \lim_{n\to\infty} \int_0^1 \int_0^1 \cdots \int_0^1 \{ x_1 + x_2+ \cdots + x_{n} \} \ dx_1 \ dx_2 \cdots dx_n $$ where $\{x\}$ - the fractional part of $x$.
It's absolutely magnificent to work on the area of limits consisted of multiple integrals. I need to create more stuff like that.
 
7:53 PM
@r9m I have added a more analytic interpretation of the probabilistic argument.
 
r9m
@robjohn :) .. honestly I don't understand anything about probability and distributions ..
 
Anyone willing to help me understand an apparently mad calculation regarding Glasser's method?
In algebra, a Bring radical or ultraradical of a complex number a is a root of the polynomial :x^5+x+a. \, The root is chosen so the radical of a real number is real, and the radical is a differentiable function of a in the complex plane, with a branch cut along the negative real line below âˆ’1. George Jerrard showed that some quintic equations can be solved using radicals and Bring radicals, which had been introduced by Erland Bring. They can be used to obtain closed-form solutions of quintic equations. Normal forms The quintic equation is rather difficult to obtain solution...
I don't get the point of $\psi_n(q)$ at all.
 
It's not funny.
 
@r9m ah, sorry. I think I have a post that gives an intuitive idea of how the CLT works...
 
8:04 PM
@BalarkaSen I posted above a limit you might like. I hope you don't miss it.
 
All this math is too deep for me.
 
@Chris'ssis Sorry, no time to do that one. I have a more complicated thing at hand lately.
 
@BalarkaSen No need to do that. At least to see it and admire it. :-)
 
OK, let's see what it is about.
Hmm, weird thing you have there, @Chris'ssis
 
@BalarkaSen It's marvellous.
 
r9m
8:09 PM
@robjohn looks like you slayed Smaug the terrible .. can you please link me to how the CLT works ?
 
@r9m I know who is Smaug, dude.
@Chris'ssis Let me think. Fractional part inequalities + Fubini's theorem?
 
...or not.
 
What is the bibliography really supposed to contain ?
 
References.
 
8:12 PM
To what?
 
Other books.
Or papers.
Or letters
Or CAS codes
 
I only have toilet papers
 
If I use theorems or quote lemmas I include references to them
But what about (you can read more about topic X in Y)
 
@N3buchadnezzar references*
 
Like that, yes.
@N3buchadnezzar That is also used.
 
8:14 PM
@r9m this answer is the one I was mentioning
 
But is it kocher to cite books you have not read?
 
Kosher.
 
Not really.
It's a way of avoiding getting too broad.
 
I always quote books I have not fully read.
 
If I know - and I have seen - a proof of X in Y, and I know the exact page/theorem number then...
 
8:15 PM
What's the problem?
 
Just quote it
 
Yeah. And put reference to the page and stuff.
 
r9m
@robjohn Arigato :)
 
@Will Toiletpaper mathematicians are the real mathematicians.
Get a pen, pick a toilet paper and do the real math instead of gulping things from internet.
That's mathematics.
 
8:17 PM
I probably can't do maths then..
I have an odd student, while everyone else just accept what I say without ever questioning it (sadly when I make mistakes as well), every single thing I say or state his automatic response is "no" or "no it's not true", then I argue with him until he realises and he apathically responds "ah okay"
 
That is the real student, dude.
He learns things.
 
Precisely, he learns that way.
 
The other gulps them.
 
Doesn't 'eat' them.
Yeah.
Still would be nicer to hear "why" instead of "no", but you can't have it all..
 
@Studentmath I agree with you on that one.
@robjohn A little help here?
 
8:23 PM
@BalarkaSen with?
 
I don't understand the idea behind $\psi_n(q)$
I know gauss multiplication theorem but don't understand how the summand becomes that thing multiplied by $_{N+1}F_N$ stuff.
Perhaps you can help, @robjohn?
 
@BalarkaSen I have never looked at that stuff... I can take a look
 
Yes, take a look please. The concept is not hard, but the calculations are complicated.
I never took a look at it carefully enough until now.
So this should be a lesson for me : Never judge an apple by it's peel.
 
@BalarkaSen oh, that is hypergeometric stuff... I have stayed away from that.
3
 
Oh no
 
8:39 PM
@BalarkaSen Well you need to cite things. Cause then you can say things like: "Euler proved in 1733 [4] ... but just with pen and paper on the loo I generalized that into something much greater".
 
r9m
8:55 PM
@Chris'ssis $\displaystyle \int_0^1 \cdots\int_0^1 \{x_1+\cdots+x_n\}\,dx_1\cdots\,dx_n = \int_0^1 \cdots\int_0^1 x_2+\cdots+x_n\,dx_2\cdots\,dx_n = \frac{n-1}{2}$ :D
 
@r9m you suggest my limit tends to $\infty$?
 
r9m
@Chris'ssis yas . it does :P
 
@r9m No, it doesn't.
 
r9m
@Chris'ssis OOPS !! .. fractonal part .. sorry .. it converges nicely
 
9:00 PM
@r9m ;)
 
r9m
@N3buchadnezzar I loved it :) .. especially the cat one
@N3buchadnezzar Cat Drop
 
@r9m Just saw it
 
@r9m There is a way to finish that without pen and paper in one single line.
 
r9m
@Chris'ssis ya I tried to act like knight Lancelot .. without pen and paper .. that messed me up ;P
@Chris'ssis how did you do it ?
 
9:13 PM
@r9m I'll tell you later on. Maybe you wanna look at some obvious things firstly. :-)
 
r9m
@Chris'ssis okay
@Chris'ssis i guess the idea is $\displaystyle \int_0^1 \{x_1+x_2\}\,dx_1 = \int_0^1 x_1+x_2 - [x_1+x_2]\,dx_1 = x_2 + \frac{1}{2} - \int_0^1 [x_1+x_2]\,dx_1 = x_2 + \frac{1}{2} - x_2 = \frac{1}{2}$
 
9:30 PM
@robjohn You are moderator, so, this user math.stackexchange.com/users/135375/markfd is deleting his questions.
 
@Cortizol okay, I'll look into it. Thanks
@Cortizol they evidently want to be deleted, so they are trying to take their contributions with them.
 
@r9m let the variable change $x_i\mapsto 1-x_i$ and the integral you get you add to the initial integral and then divide by 2. Q.E.D.
 
@Cortizol it won't do much good to punish them as their account will probably be gone soon anyway.
 
r9m
@Chris'ssis nice :)
 
@r9m This is what I had in mind when I created it. Thanks.
 
r9m
9:42 PM
@Chris'ssis is my approach ok ?
 
@r9m It's not bad. When using more variables you need to explain some things there that might look uglier. Well, it can be improved, surely, to make it look good.
 
r9m
@Chris'ssis we just replace the $x_2$ with $(x_2+\cdots+x_n)$ .. the rest is same as before :)
 
@r9m Indeed.
 
hmm, is 2 a primitive root mod 3^k for all k?
 
@seaturtles $$2^{2\cdot 3^m} = 4^{3^m} = (1+3)^{3^m} \equiv 1 + 3^{m+1} \pmod{3^{m+2}}$$
 

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