даны множества A= {-4, -(-5), 0, 7, 21} и B= {5, -(-7), 18, -8, 15} найдите AUB; AnB; A\B; B\A.

AUB={-4,5,0,7,21,18,-8,15}

AnB={5,7}

A\B={-4,0,21}

B\A={18,8,15}