Prove that: .
Here is the question at this link: Yfrog Image : yfrog.com/m9setsp
So here's what I've done so far: I know the A with the little hat on top means everything outside of A ie the universe. Now I know that A u B with the hat over all of that is A n B with hats over A and B only. So there's now A with 2 hats? Does that just mean A? If so, then it is A n B with a hat only over B. My answer to that is an empty set. Please help! I've done something wrong here!
Thanks in advance.