Question

集合A有三个元素,集合B有二个元素,问从A到B的映射有几个

Answer 1

8个 2的3次方个

射A{a,b,c,}B{m,n}

1 A{a,b,c} B{m,m,m}

2 A{a,b,c} B{n,n,n}

3 A{a,b,c} B{m,m,n}

4 A{a,b,c} B{m,n,n}

5 A{a,b,c} B{n,m,m}

6 A{a,b,c} B{n,n,m}

7 A{a,b,c} B{n,m,n}

8 A{a,b,c} B{m,n,m}