Question

集合A={1,4,3},B={2,5,4},求A∩B={4} A∪B ={1,2,3,4,5}

Answer 1

A∩B={x|x∈A且x∈B}；A∪B={x|x∈A或x∈B}
则：
A∩B={4}、A∪B={1,2,3,4,5}