Prove:

(A-B)union(B-A)=(AunionB)-(AintersectB).

We need to show (A-B)union(B-A)is contained in(AunionB)-(AintersectB)

and (AunionB)-(AintersectB)is a superset of (A-B)union(B-A).

We begin by showing the first:

Let x be an element of(A-B)union(B-A).

By definition of union, x is inA-B or xis not in B-A.

If xis in A-B, we know xis an element of A and x is not an element of B.

This is where I've begun to get stuck. Not sure where to go next.