prove $\text{abs}(a + b) + \text{abs}(a - b) = \text{max}(a, b) \cdot 2$
58629
Show that the $\max{ \{ x,y \} }= \frac{x+y+|x-y|}{2}$.
111515
Proving that $-a=(-1)\cdot a$
63958
how to prove this inequality $(ab+bc+ac)^2 ≥ 3abc(a+b+c)$
8589
$\sqrt[b_1]{a_1}+\sqrt[b_2]{a_2}+\cdots+\sqrt[b_k]{a_k}$ not an integer
38404
Prove $\gcd(a+b, a-b) = 1$ or $2\,$ if $\,\gcd(a,b) = 1$
139503
How to prove $|a+b|^k \leq 2^{k-1} (|a|^k+|b|^k)$?
24856
Proving sup(A + B) = sup A + sup B
127296
prove that a|b and b|a iff a=+-b
153823
$|\text{rank}A-\text{rank}B|\leq \text{rank}(A+B)$
105367
Proving $||\vec{a}+\vec{b}|| = ||\vec{a}-\vec{b}|| \iff \vec{a} \perp \vec{b}$
43310
Proving $A\cap(B-C)$ is equal to $(A\cap B)-(A\cap C)$
157268
Proving a bijection with absolute value
21288
For integers $a$ and $b$, $ab=\text{lcm}(a,b)\cdot\text{hcf}(a,b)$
6410
Prove that $(ma, mb) = |m|(a, b)\ $ [GCD & LCM Distributive Law]
133699
Proving that there is a bijection between $A$ and $B$.
20110
How to prove $(AB)^T=B^T A^T$
150609
Triangle Inequality of the Cartesian product with Max function