1.已知f(x)=(x-2)/(x+2),则f-1(1/x)为?

问题描述:

1.已知f(x)=(x-2)/(x+2),则f-1(1/x)为?
2.已知f(x)=2x-3,则f-1[f(x)]为?

1.首先反解f(x),得出f-1(x)=(2x+2)/(1-x)
带入x'=1/x,得f-1(1/x)=(2+2x)/(x-1)
2.同样反解f(x),得f-1(x)=(x+3)/2
带入x'=f(x)=2x-3,得出f-1[f(x)]=x