Proof by induction Watch
Hey is it just using N=1,n=k and n=k+1, and then proving it works. Is that all there is to proof by induction or is there more to know?
You show that it's true for the base case (usually n=1), assume that it's true for k and then prove it for k+1. (The way this works is that you've proved that it works for 1, and that if it works for k then it works for k+1 so you know it works for 2, use that to show that it works for 3 and so on ad infinitum).
Best thing to do is familiarise yourself with it by practicing.