The operation in which we obtain the elements that are only in set A but not in set B is __________ .
B - A
A ∪ B
A - B
A + B
The operation which gives the elements that are only in set A but not in set B is A - B.
Given a non-empty set X, consider the binary operation *: P(X) × P(X) → P(X) given by A * B = A ∩ B &mnForE; A, B in P(X) is the power set of X. Show that X is the identity element for this operation and X is the only invertible element in P(X) with respect to the operation*.