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定义A-B={x|x∈A且x∉B},若P={1,2,3,4},Q={2,5},则...
定义A-B={x|x∈A且x∉B},若P={1,2,3,4},Q={2,5},则Q-P( )
A.P
B.{5}
C.{1,3,4}
D.Q
考点分析:
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