is the product of two perfect square numbers always a perfect square?

answers:
billrussell42 say: yes. easy to prove
a²b² = (ab)²
if a and b are integers, ab is also an integer, therefore (ab)² is a perfect square

zhhnh say: tqjczykk

warln say: vzorkdsb

pqldr say: usoatbsx

akhjj say: ypzrpunh

agzmg say: hzjtxufn

hjfpz say: ppthbgta
