**Guide :High School **

# Prove: For all integers n, if n2 is odd, then n is odd. Use a proof by contraposition, as in Lemma 1.1.

Prove: For all integers n, if n2 is odd, then n is odd. Use a proof by contraposition, as in Lemma 1.1.**The contrapositive of above is "If n is not odd then n^2 is not odd" or "If n is even then n^2 is even".So, let assume that n is eventhen which is even q.e.d.**...