1. Prove each of the following for all n > 1 by the Principle of Mathematical Induction. a) 1 + 3 +5 +.... b) 1.3 +2.4 +3.5 +...+n(n + 2) = n(n + 1)(2n + 7) 6 + (2n 1)2 = n(2n 1)(2n + 1) 3 1 ii + 1) 4 n + 1 ni(n + 1)2 (2) = ;=1