# mhd.math

Damascus, Syria

interested in math and modern physique

Top Questions
44 votes

## Is there a function with the property$f(n)=f^{(n)}(a)$

asked May 20 '13 at 17:42

30 votes

## Find closed form for $1, 2, 2, 3, 4, 4, 5, 6, 6, 7, 8, 8, 9, 10, 10, \ldots$

asked Jun 19 '13 at 21:45

19 votes

## Finding the fraction $\frac{a^5+b^5+c^5+d^5}{a^6+b^6+c^6+d^6}$ when knowing the sums $a+b+c+d$ to $a^4+b^4+c^4+d^4$

asked May 26 '13 at 12:41

15 votes

13 votes

13 votes

## closed form of $\int_{0}^{2\pi}\frac{dx}{(a^2\cos^2x+b^2\sin^2x)^n}$

asked Jul 29 '13 at 20:39

11 votes

10 votes

## Evaluate $\lim_{x \to 0} \frac{x^2}{x+\sin (\frac 1 x)}$

asked May 2 '13 at 17:00

9 votes

## Find the limit without use of L'Hôpital or Taylor series: $\lim \limits_{x\rightarrow 0} \left(\frac{1}{x^2}-\frac{1}{\sin^2 x}\right)$

asked May 23 '13 at 19:18

9 votes

## show that $\int_0^{\infty}\sin(u\cosh x)\sin(u\sinh x)\frac{dx}{\sinh x}=\frac{\pi }{2}\sin u$

asked Jan 22 '15 at 12:53