Prove that A XOR B AB UNION BASolutionAB means objects that

Prove that

A XOR B = (A-B) UNION (B-A)

Solution

A-B means objects that belong to A and not to B
B-A means objects that belong to B and not to A
(A-B) union (B-A) is then objects that belong to A or B but not to their intersection
which is the definition of symmetric difference or exclusive or