Question

Define a,b in IR^n as follows
For every i in 1....n (a)=(-1)^(i-1) i.e. a=(1,-1,1,-1...)
For every i in 1....n (b)=(-1)^i i.e. b=(-1,1,-1,1....)
Compute: IIaII, IIbII, angle (a,b)

Answer 1

I feel like this has something to do with using k+1 and k. If that makes any sense