第2课时补集及综合应用分层演练综合提升A级基础巩固1.(全国卷Ⅰ)若集合U={1,2,3,4,5,6,7},A={2,3,4,5},B={2,3,6,7},则B∩(∁UA)=()A.{1,6}B.{1,7}C.{6,7}D.{1,6,7}答案:C2.若集合A={1,5,7},B={x∈Z|1≤x≤7},则∁BA=()A.{2,4,6}B.{2,3,4}C.{2,3,4,6}D.{2,3,4,7}答案:C3.若全集U={1,2,3,4,5,6,7,8},集合A={1,2,3,4},B={2,4,6,8},则(∁UA)∩(∁UB)=()A.{5,7}B.{1,5,7}C.{2,4}D.{1,2,3,4,6,8}答案:A4.若全集U=R,集合A={x|x≥3,或x≤0},则∁UA={x|0
2}.(1)求A∩B,(∁RB)∪A;(2)若集合C={x|12},所以A∩B={x|21,a≤3,解得14},∁RB={x|x≥0},所以A∩B=⌀,A∪B={x|x<0,或13}.答案:BC