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Don't have much time these days...


1d
comment Asymptotic Behaviour Of A Bizarre Function 2
Related: math.stackexchange.com/questions/115824/…
1d
comment Asymptotic Behaviour Of A Bizarre Function 2
@900sit-upsaday: Thanks! Wasn't aware of this nice feature. Been away from stackexchange long enough...
2d
comment How prove this $\sum_{cyc}\frac{x+y-2z}{(x+y)^2+z^2}=0$
Why is this tagged inequality?
2d
comment Polynomial representation
@Minu: Yes, that is correct.
2d
comment Polynomial representation
@Mathmo123: Don't know. Let's see Minu's response. (You might be right though)
2d
comment Prove that an expression is zero for all sets of distinct $a_1, \dotsc, a_n\in\mathbb{C}$
@DamianPavlyshyn: Yes, or more simply, replace $a_1$ by $z$, do some algebra to get a polynomial in $z$ which has infinite roots (any $z \ne a_i$), allowing setting $z=0$.
Jul
23
comment Prove that an expression is zero for all sets of distinct $a_1, \dotsc, a_n\in\mathbb{C}$
Look at the Lagrange polynomial of $P(a_i) = a_i$
Jul
19
comment Proving that one of $a(1-b), b(1-c), c(1-a) \le \frac{1}{4}$
For $a,b,c \le 1$, see my comment to DanZimm. There is no need of $c$ if $a \le b$. There is an implicity renaming of variables going on. For instance if you chose $a=0.3, b = 0.1, c = 0.4$, we kind of have implicitly swapped $b$ and $c$ in our proof...
Jul
19
comment Proving that one of $a(1-b), b(1-c), c(1-a) \le \frac{1}{4}$
@DanZimm: If $c \ge 1$, then $b(1-c) \le 0$.
Jul
19
comment Always null recurrence at the boundary between positive recurrence and transience?
Can you think of a better title?
Jul
18
comment Solving the integral $\int_{0}^{\infty} \frac{\sin{x}}{x} \ dx = \frac{\pi}{2}$?
@V-Moy: I am flattered! Glad that my answers have been helpful. :-)
Jul
18
comment Solving the integral $\int_{0}^{\infty} \frac{\sin{x}}{x} \ dx = \frac{\pi}{2}$?
@V-Moy: Thank you for your kind comments! (and the badge :-))
Jul
18
comment What is the integral of x/ln(x)?
See: en.wikipedia.org/wiki/Exponential_integral
Jul
18
comment Is the sequences$\{S_n\}$ convergent?
@Lucian: Why not cast a dupe vote if you know a question already exists?
Jul
18
comment how to solve these equation?
Related: math.stackexchange.com/questions/6965/system-of-equations
Jul
18
comment Convergence of a subsequence .
Just take any bounded sequence which does not converge.
Jul
18
comment Bounds on a recursively defined sequence
@angryavian: $\frac{e^x-1}{x} = \sum_{k=0}^{\infty} \frac{x^k}{(k+1)!}$. Differentiate twice.
Jul
18
comment Lattice Path Spaces.
Are you allowed to revisit earlier points?
Jul
18
comment Bounds on a recursively defined sequence
Is the paper trying to analyze a permutation generation algorithm and prove that it is $\theta(n!)$?
Jul
15
comment Are all existence proofs by contradiction?
Short answer to the title: No.