f(x)=1-x?
升*** 2016-07-10 00:16:17 举报
设y=(1-x)/(1+x),则y+xy=1-x, x(y+1)=1-y, x=(1-y)/(1+y), ∴f^-1[1/(1+x)]=[1-1/(1+x)]/[1+1/(1+x)] =x/(2+x).