Question

高一集合计算已知集合A={x/3≤x＜7} B={x/2＜x＜10} 求CR（A∪B),CR(A∩B) ,(CRA) ∩

Answer 1

A∩B={x/3≤X〈7},AUB={X/2〈X〈10} ,Cr(AUB)={x/x≤2或x≥10} ,

Cr(A∩B）={x/x＜3或x≥7}.

CrA={x/x＜3或x≥7},(CrA)∩B={x/2＜x＜3或7≤x＜10}.

CrB={x/x≤2或x≥10},AU(CrB)={x/x≤2或3≤X〈7或x≥10}