Hi My name is Mr William, I am a student The question is secondary I am trying to prove a induction question Sigam r=1 n (2r 1)cube = n square (2 n square  1) Thanks. Hi William,The expression you have is certainly true when n = 1. Suppose now that the expression is true for n = k  1, then for n = k, You should now be able to complete the problem.
Cheers,
