Hey there. So for induction, the inductive step is whenever you say "assume this is true for all k or k-1" In this question it is the line "Let... integer m".

Apr 25th, 2015

Do you have any questions, or would you like a reference?

Apr 25th, 2015

Well, just in case you do not understand, here is a link to khanacademy. They have a really wonderful tutorial on Induction. I also wanted to mention there are two types of induction, strong and simple. Your question utilizes simple induction.