Question

已知集合 A=｛x|x=3n+1,n∈z} B=｛x|x=2n+1,n∈z} 求A∩B

Answer 1

A∩B=｛x|x=3n+1,n∈z} ∩｛x|x=2n+1,n∈z}={y|y=6n+1,n∈z}