Originally Posted by

**uberbandgeek6** I don't have any experience dealing with binomial coefficients, so I'm really confused on how to do this following problem. I wrote the binomial coefficients in parenthesis with some space between where the top and bottom part should be (not sure how to format it otherwise

Problem: Prove that

n

Sigma (n i) = 2^n

i=0

and

n

Sigma (-1)^n * (n i) = 0

i=0

I'm not sure if I need to use induction or not to prove either of these and I'm not sure where I'd start even the base of induction if I did have to.