题干

已知集合A={1,2,3,x},B={3,x2},且A∪B={1,2,3,x},求x的值.

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答案(点此获取答案解析)

解:(1)当x2=x时,x=0或x=1,

当x=0时,符合题意,当x=1时,集合A违背集合中元素的互异性,

故x=0;

(2)当x2=1时,x=﹣1或x=1,

当x=﹣1时,符合题意,当x=1时,集合A违背集合中元素的互异性,

故x=﹣1;

(3)当x2=2时,x=-

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根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

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