问题 选择题
设全集I={1,2,3,4,5,6,7},集合A={1,3,5,7},B={3,5}.则(  )
A.I=A∪BB.I=
.
A
∪B
C.I=A∪
.
B
D.
.
A
.
B
答案

因为全集I={1,2,3,4,5,6,7},B={3,5},

所以

.
B
={1,2,4,6,7},又A={1,3,5,7},

则A∪

.
B
={1,2,3,4,5,6,7}=I.

故选C

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