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Math.SE seems to be going the stackoverflow way. Pity.


17h
comment Help with $\lim_{x\rightarrow +\infty} (x^2 - \sqrt{x^4 - x^2 + 1})$
You are welcome.
1d
comment Proving that $\sin1 $(radian) is irrational without using Taylor Series Expansion.
btw, if it was $\sin 1^{\circ}$, the proof would be easy: $\sin 45^{\circ}$ is a polynomial in $\sin 1^{\circ}$ with rational (in fact, integer) coefficients! Since $\sin 45^{\circ}$ is irrational...
1d
comment Irrational numbers in reality
This is not a mathematical question. Seems like you found a bug around getting close votes by offering a bounty :-) I have flagged for migration to physics.se, so let's see.
2d
comment Can't figure out $O(n \log n)$ divide-and-conquer algorithm
You could implement so it is $\Omega(n \log n)$ instead of $O(n)$ though...
2d
comment Can't figure out $O(n \log n)$ divide-and-conquer algorithm
This is the famous maximum sum subarray problem...
2d
comment Why $\frac{1}{n}\sum_{j=1}^mj^p \asymp\frac{1}{n}m^{p+1}$ as $n\to\infty$?
@Lionville: Ok, good to know you haven't ignored it completely :-)
2d
comment How to proceed with the following integration?
Manish, this site has latex support using MathJax, please use it instead of posting image links. Here is a reference: meta.math.stackexchange.com/questions/5020/…
2d
comment Calculating Euler's totient function values.
@Amad27: Once you solve this yourself (based on OohAah's comment), please add an answer and tick that.
2d
comment Calculating $\sum_{k=0}^{n-1}\frac{1}{a+bk^2}$.
A closed form is unlikely, but you can try and use Euler-MacLaurin Summation formula, which is beyond algebra-precalculus.
Jan
27
comment Number of real roots of $2 \cos\left(\frac{x^2+x}{6}\right)=2^x+2^{-x}$
@mathamphetamines: The question is asking for the number of real roots. What prevents it from being 42 or infinity or etc?
Jan
26
comment Remove minimal number of elements
Search the web for sum free subsets.
Jan
25
comment Seperating points in the complex plane
@MarkMcClure: Yeah, I guessed that (smiley and all :)). Just wanted to make you aware of that meta thread, that's all. There are reasons to post an answer instead of a comment, even if you think it is trivial etc. Sorry if my comment sounded like an accusation. It was not.
Jan
25
comment Relationship between increasing integer sequences
btw, using density arguments, the answer is probably yes.
Jan
25
comment Solve recurrence relation merge sort
What do you mean by "solve" exactly? Find out whether $a(n) = \Theta(n \log n)$? Or some exact formula etc?
Jan
25
comment Relationship between increasing integer sequences
Are you trying to prove the converse of Beatty's theorem?
Jan
25
comment Seperating points in the complex plane
@MarkMcClure: Why post an answer as a comment? Post it as an answer. user86418 is doing the right thing: meta.math.stackexchange.com/questions/1559/…
Jan
25
comment Why is this sum wrong?
@Redding: The example I gave you is a good example. But the simplest reason is that the theorems you use to justify taking individual limits only involve finite number of terms, independent of $n$. There are no such theorems when the number of terms is dependent on $n$.
Jan
23
comment Evaluating $\lim_{n\to\infty} e^{-n} \sum\limits_{k=0}^{n} \frac{n^k}{k!}$
[Older question, perhaps merge...] possible duplicate of Partial sums of exponential series
Jan
21
comment Comparing $\pi^{e}$ and $e^{\pi}$
@MurtuzaVadharia: Yes, it is true. Consider $f(x) = e^x -1 -x$. It's derivative is $e^x -1$ which is $\lt 0$ for $x \lt 0$ and $\gt 0$ for $x \gt 0$, so $f$ decreases from $-\infty$ to $0$, and increases from $0$ to $\infty$. Since $f(0) = 0$...
Jan
14
comment Linear Combinations of Fibonacci Numbers (integer coefficients)
@theage: No worries. At least you even bothered to respond to my comments. Some folks don't even care :-) I suggest you wait at least a couple of days before even thinking about accepting. By accepting an answer too soon you cut down on the number of folks who will even see the question.