摘要:1. 1.设集合P = {1.2.3.4.5}.Q = {}.则等于( ) A.{1.2} B.{– 2.– 1.0.1.2} C.{1.2.3.4} D.{1}
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设集合P={1,2,3,4,5,6,7,8,9,10},P的子集A={a1,a2,a3},其中a1<a2<a3,当满足a3≥a2+3≥a1+6时,称子集A为P的“好子集”,则P的“好子集”的个数为
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