已知全集U={1,2,3,4,5,6,7},A={2,4,5},B={1,3,5,7}.
(1)求A∪B;
(2)求(∁UA)∩B;
(3)求∁U(A∩B).
解:全集U={1,2,3,4,5,6,7},A={2,4,5},B={1,3,5,7}.
(1)A∪B={1,2,3,4,5,7}
(2)(∁UA)={1,3,6,7}
∴(∁UA)∩B={1,3,7}
(3)∵A∩B={5}
∁U(A∩B)={1,2,3,4,6,7}.
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