已知全集U={1,2,3,4,5,6},集合M={3,4,5,6},N={1,2,3,4},则M∪CN=

Question

已知全集U={1,2,3,4,5,6},集合M={3,4,5,6},N={1,2,3,4},则M∪CN=

Answer 1

1.CuM的意思就是,在集合u中,除去M以外的元素的集合,{1,2,3,4,5,6}中,除去{1,3,5},就是{2,4,6}啦,{2,4,6}交{2,4,6},当然还是{2,4,6},所以CuM∩N=N.
2.a={1,2},a∪b={1,2,3},b集合可能是{1,2,3},{1,3},{2,3},{3},所以个数为4个.
3.a={0,2,4,6},CuA={-3,-1,1,3},集合u={-3,-1,0,1, 2,3, 4,6},CuB是u中除去-1,0,2三个元素,剩下的当然就是-3,1,3,4,6.