[题目]集合M＝{1,3.a}.N＝{2.a2}．若M∪N＝{1,2,3,4,16}.则a的值为( )A．0 B．1 C．2 D．4 题目和参考答案——青夏教育精英家教网—

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【题目】集合M＝{1,3，a}，N＝{2，a2}．若M∪N＝{1,2,3,4,16}，则a的值为（）

A．0 B．1 C．2 D．4

【答案】D

【解析】∵M＝{1,3，a}，N＝{2，a2}，M∪N＝{1,2,3,4,16}，∴a=4，a2=16或a=16，a2=4，解得a=4．

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