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已知集合A={1,2},B={2,4},则集合M={z|z=x•y,x∈A,y∈...
已知集合A={1,2},B={2,4},则集合M={z|z=x•y,x∈A,y∈B}中元素的个数为( )
A.1个
B.2个
C.3个
D.4个
考点分析:
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