So here's the question :

Let

A = {n ∈ N : the last digit of 2^n is 8},

B = {n ∈ N : n+1 is divisible by 4}.

Show that A = B.

Now i understand what this question is saying and i understand that A does in fact = B. But i have no idea how to prove this... Any hints or help would be much appreciated.

Thank you!!!