问答题
用区间表示适合下列不等式的变量x的变化范围:
设A,B都是集合U={1,2,3,4,5,6,7,8,9,}的子集,且AC∩BC={1,3,7,9},试求A∪...
问答题设A,B都是集合U={1,2,3,4,5,6,7,8,9,}的子集,且AC∩BC={1,3,7,9},试求A∪B。
设U={1,2,3,4,5,6,7},A={2,3,4},B={3,6,7},求AC,BC,AC∩BC,(A∪...
问答题设U={1,2,3,4,5,6,7},A={2,3,4},B={3,6,7},求AC,BC,AC∩BC,(A∪B)C