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user49685
  • Member for 11 years, 6 months
  • Last seen more than 1 year ago
56 votes

Product of inverse matrices $ (AB)^{-1}$

17 votes

Integration of a function with respect to another function.

9 votes
Accepted

Prove that $\sin 10^\circ \sin 20^\circ \sin 30^\circ=\sin 10^\circ \sin 10^\circ \sin 100^\circ$?

7 votes
Accepted

Is this sloppy writing for limits?

6 votes
Accepted

integration by parts from Apostol

6 votes
Accepted

Factorizations of $x^2+x$ in $\mathbb Z_6[x]$

6 votes
Accepted

Order of $\mathbb{Z}[i]/(1+i)$

6 votes
Accepted

Number of terms in the expansion of $\left(1+\frac{1}{x}+\frac{1}{x^2}\right)^n$

5 votes

Find the value of $\sin\frac{2\pi}{7}+\sin\frac{4\pi}{7}+\sin\frac{8\pi}{7}$

5 votes

Prime ideal and nilpotent elements

4 votes

Repeating Decimals

4 votes
Accepted

Polynomials over a field having equal polynomial functions

4 votes

Finite rings and subrings isomorphic to $\mathbb{Z}_n$

4 votes
Accepted

Proof of the First Isomorphism Theorem for Rings

3 votes
Accepted

Union of Subgroups

3 votes

Find the limit $\lim_{x\rightarrow 0} \frac{\sin x - x}{\tan x - x}$

3 votes

Is this function differentiable at 0?

3 votes
Accepted

Absolute values in $\int \frac{dx}{(x+2)\sqrt{(x+1)(x+3)}}$

3 votes
Accepted

Cancellation propriety for continuous functions.

3 votes

prove an integral reduction formula for $\cos^{m}x/\sin^{n}x$

3 votes
Accepted

For subspaces, if $N\subseteq M_1\cup\cdots\cup M_k$, then $N\subseteq M_i$ for some $i$?

2 votes

$\lim_{t \to 0}g(t)=10$ $\lim_{t \to 10}f(t)=100$ but $\lim_{t \to 0}f(g(t))$ does not exist

2 votes
Accepted

Under what conditions are the variables $a, b$ satisfying $A \cap B = \emptyset$ and $A \cap B = \{0\}$

2 votes

H0w t0 prove that periodic decimal numbers are rational? $a_1...a_k(b_1b_2..b_l)={m \over n}$

2 votes

Can anyone explain why $a^{b^c} = a^{(b^c)} \neq (a^b)^c = a^{(bc)}$

2 votes

Limit of a n-root

2 votes
Accepted

when $f(x)^n$ is a degree of $n$ why is useful to think $\sqrt{f(x)^n}$ as $n/2$?

2 votes
Accepted

Algebraic closure of $\mathbb{Q}$ and $\mathbb{R}$

1 vote

Prove that $n$ is even.

1 vote

Is this sequence $x_{n+1}=1+\frac{a-1}{1+x_n},$ with $a>1, x_1>0$, convergent or divergent?