user avatar
user avatar
user avatar
M.H
  • Member for 9 years, 8 months
  • Last seen more than 3 years ago
58 votes

Do matrices $ AB $ and $ BA $ have the same minimal and characteristic polynomials?

30 votes

Let $H$ be a subgroup of a group $G$ such that $x^2 \in H$ , $\forall x\in G$ . Prove that $H$ is a normal subgroup of $G$

23 votes
Accepted

First and second derivative of a summation

19 votes

Evaluating the derivative of $\large \;e^{e^x}$?

15 votes

cosh x inequality

10 votes
Accepted

$AB-BA$ is a nilpotent matrix if it commutes with $A$

9 votes

Proving that $\int_a^b\frac{dx}{\sqrt{(x-a)(b-x)}}=\pi$

8 votes

If two functions go to infinity at zero, does the difference go to zero?

8 votes

How to find $p$ when $ ({\frac{1}{2}})^p + ({\frac{1}{4}})^p + ({\frac{1}{8}})^p - 1 = 0. $

7 votes

Why does $\sum_{n = 0}^\infty \frac{n}{2^n}$ converge to 2?

6 votes

Prove that $ n < 2^{n}$ for all natural numbers $n$.

6 votes

Sylvester rank inequality: $\operatorname{rank} A + \operatorname{rank}B \leq \operatorname{rank} AB + n$

6 votes

Prove $|\frac{1}{n} - \frac{1}{x}| \le \frac{1}{n^2}$

6 votes

Derivative of ${x^{x^2}}$

5 votes

Given two subspaces $U,W$ of vector space $V$, how to show that $\dim(U)+\dim(W)=\dim(U+W)+\dim(U\cap W)$

5 votes

Find $f(x)=?$ functional equation

5 votes
Accepted

Calculating determinant of a block diagonal matrix

5 votes

Show $\cos(x+y)\cos(x-y) - \sin(x+y)\sin(x-y) = \cos^2x - \sin^2x$

5 votes

Indefinite integration : $\int \frac{1+x-x^2}{\sqrt{(1-x^2)^3}}$

4 votes

Determine the determinant and the inverse to the matrix A.

4 votes
Accepted

Does $i = -\frac{(2\;W({\pi\over2}))}{\pi}$

4 votes

How to integrate $\int \frac{1}{\cos(x)}\,\mathrm dx$

4 votes

Proof of $A\cap(B\cup C) = (A\cap B)\cup(A\cap C)$

4 votes

Integration of trig - reduction formula $\int \cos^4 x\; dx$

4 votes

Find the value of $\large i^{i^{.^{.^.}}}$

4 votes

Hyperbolic Integral

4 votes
Accepted

Exponentials, Logarithms & the Natural Log

4 votes

How to show that linear map is invertible?

3 votes
Accepted

What does this sign mean?

3 votes

Ordered Pair Formal Definition

1
2 3 4 5 6