CuA={3,6,7,8,10},CuB={1,2,3,5,9},CuA∩CuB={3},CuA∪CuB={1,2,3,5,6,7,8,9,10},Cu（A∪B)={3},Cu（A∩B）={1,2,3,5,6,7,8,9,10},相等的集合：CuA∩CuB=Cu（A∪B)