If $\gcd(a, b) = 1$ then $\gcd(ab, a+b) = 1$?
20878
If $(a,b)=1$ then prove $(a+b, ab)=1$.
122096
Find $GCD(n^2+1,n+1)$
1991
If $\gcd(a,b)=1$ and $a$ and $b$ divide $c$, then so does $ab$
25713
If $a$ and $b$ commute and $\text{gcd}\left(\text{ord}(a),\text{ord}(b)\right)=1$, then $\text{ord}(ab)=\text{ord}(a)\text{ord}(b)$.
108450
Prove that $\gcd(a, b) = \gcd(a, b + ma)$?
8160
What is $\gcd(0,a)$, where $a$ is a positive integer?
25573
If $\gcd(a,b)=1$, then $\gcd(a+b,a^2 -ab+b^2)=1$ or $3$.
55673
Alternate proof that $\exists\ x \in \Bbb{Z}$ such that $ \gcd (a+bx,c) = 1$?
18714
$\gcd\left(a+b,\frac{a^p+b^p}{a+b}\right)=1$, or $p$
5708
Prove that if $k\ge 1\,$ and $\,a^k\equiv 1\pmod{\! n}$ then $\gcd(a,n)=1$
72424
Suppose 1 ≤ k ≤ n − 1 and gcd(k, n) = 1. Prove that gcd(n − k, n) = 1
7090
Show that $\gcd(a,bc)=1$ if and only if $\gcd(a,b)=1$ and $\gcd(a,c)=1$
95889
Prove that $\gcd(n! + 1, 3n! + 1) = 1$, $\forall n \in \mathbb{N}$, $n \geq 2$.
76680
Prove that if $\gcd(a,c)=1$ and $\gcd(b,c)=1$ then $\gcd(ab,c)=1$
1197
Finding $\gcd(2n-1,2n+1)$ . . . I think it's 1 but is my logic right?
2208
$\gcd(a,b,c)=\gcd(\gcd(a,b),c)\,$ [GCD Associative Law]
90480
Code for (a,b) with gcd(a,b)=1?