问题
解答题
设全集U={x|x是不超过10的正整数},A={x|x是偶数且x∈U},B={x|x是正质数 (也叫素数)且x∈U},
求①A∩B ②A∪B ③(CuA)∩(CuB)
答案
U={1,2,3,4,5,6,7,8,9,10},A={2,4,6,8,10},B={2,3,5,7},
因此①A∩B={2},②A∪B={2,3,4,5,6,7,8,10},③(CuA)∩(CuB)={1,3,5,7,9}∩{1,4,6,8,9,10}={1,9}