1.设全集U={3,2a-1,a^2-a+2},若集合A={3,a+2},CuA={8},则实数a的值是__ 2.设A,B,C是三个集合,若A⊆B∪C,则A⊆B或A⊆C.举例说明这命题是假命题.

设全集U=｛2,3,a²+2a-3｝……设全集U=｛2,3,a²+2a-3｝,A=｛a+1|,2﹜,A的补集=﹛5﹜,求a 设全集U=R,集合A={xl-2 设全集U=R,A={x|2 设全集U=R,集合A={x|-2 设全集U=R,A={x|-2 设全集U=R,A{x|2 设全集u=R集合A 设全集U={1,2,3,4,5},A={2,3,4},则C∪A= 设全集U=｛1,2,3,4,5｝,其子集A=｛5,1｝则A∩CUA 设全集U={2,3,a^2+2a-3}A={|2a-1|,2},CuA={5} 求集合{a,a^2}的子集个数 设全集U={3,4,a²+2a-3},集合A={a+1,2a},CUA={5},求a的值, 设全集U=｛3,4,a平方+2a-3},集合A=｛a+1,2a},｛5｝,求a的值 设全集U=R,集合A={x｜｜2x-1｜+｜x-2｜ 设全集U=R,集合A={x｜｜2x-1｜+｜x-2｜ 设全集U=R,A={x||2x-3| （1）设全集U=R,集合A=｛x｜2 设全集U=R,集合A={x|2x-1 设全集U=R,M={x|3a