问题补充:
设集合A={a,b,c},B{1,0,-1}映射f:A?B满足f(a)-f(b)=f(c)则映射f:A?B的个数有A.4个B.5个C.6个D.7个
答案:
D解析f(a)=f(b)+f(c),1=1+0,-1=-1+0,0=-1+1,0=0+0.故个数为2+2+2+1=7个.
时间:2024-06-02 13:03:47
设集合A={a,b,c},B{1,0,-1}映射f:A?B满足f(a)-f(b)=f(c)则映射f:A?B的个数有A.4个B.5个C.6个D.7个
D解析f(a)=f(b)+f(c),1=1+0,-1=-1+0,0=-1+1,0=0+0.故个数为2+2+2+1=7个.