题目内容
设U={1,2,3,4,5}, A={1,2,3}, B={2,4}, 则A∪ =
【解析】略
设U={1,2,3,4,5}, A={1,2,3}, B={2,4}, 则A∪ = ▲ .
设U="{1,2,3,4,5}," A="{1,2,3}," B="{2,4}," 则A∪ =