# Math Help - Proof Technique

1. ## Proof Technique

Im having trouble with this proof:
Let n be an integer, prove that if n^2 is divisible by three then n is divisible by three.

2. Originally Posted by jsteel2
Im having trouble with this proof:
Let n be an integer, prove that if n^2 is divisible by three then n is divisible by three.
Simply substitute in $n:=3m$, and evaluate using the fact that $(ab)^x = a^xb^x$.