Prime Division HELP!!!

PennState666

1. The problem statement, all variables and given/known data

I need to be able to understand and likely prove that for any positive odd integer n,
8 | (n^2 -1 )

2. Relevant equations



3. The attempt at a solution
odd can be said to be n = 2k +1
so 8 | (2k + 1)^2 -1

phyzguy

Keep going. Now expand out (2k+1)^2 - 1 and collect terms. Then think about the terms in k and k+1.

PennState666

I got stumped trying mathematical induction i was hoping for a new approach

Mark44

Try the approach that phyzguy is suggesting.