prove that a|b and b|a iff a=+-b
46286
Prove if $a\mid b$ and $b\mid a$, then $|a|=|b|$ , $a, b$ are integers.
101803
A\(B∩C) = (A\B) ∪ (A\C) how to prove?
21737
If $A|B$ and $B|A$ then prove $A=\pm B$
110703
How Can I prove (a+b) mod m = (a mod m) + (b mod m)) mod m?
38404
Prove $\gcd(a+b, a-b) = 1$ or $2\,$ if $\,\gcd(a,b) = 1$
24098
Prove that $a$ divides $b$ and $b$ divides $a$ if and only if $a = \pm b$
149287
Prove that $A,B>0$ and $A_{ij}0$
107173
If $a\lt{b}$ and $c\le{d}$, prove that $a+c\lt b+d$
151852
How to prove $A \subset B \iff A \cup B = B$
80255
How to prove that $|a-b|<\epsilon$ implies $|b|-\epsilon<|a|<|b|+\epsilon$?
77164
If $a \mid m$ and $(a + 1) \mid m$, prove $a(a + 1) | m$.
153670
Prove that if $a \mid b$ and $b \mid c$, then $a \mid c$.
150738
Proof of $(A - B) - C = A - (B \cup C)$
27281
How to prove $\,x^a-1 \mid x^b-1 \iff a\mid b$
43310
Proving $A\cap(B-C)$ is equal to $(A\cap B)-(A\cap C)$
70311
Trying to prove (A ∩ B) − C = (A − C) ∩ (B − C)
5369
Proving the inequality $|a-b| \leq |a-c| + |c-b|$ for real $a,b,c$