Proofs

1 Proofs 1.1 Show The number n2 5n 5 is odd. (Proof by Induction) 1.2 Prove that the product of two odd natural numbers must be odd (Direct Proof) 1.3 Prove that if n is an even naural ber an if m is any natural number then n * m must be even. (Direct Proof) 1.4 Prove that the cube of an odd number must be odd. (Direct Proof)