解由f(x)=(x-1)^(-2) =1/(x-1)^2 （x≠1）则f'(x)=｛1'[(x-1）^2]-1×[(x-1）^2]'｝/(x-1)^4=｛-1×[2(x-1）^1]（x+1）'｝/(x-1)^4=｛-1×[2(x-1）^1]｝/(x-1)^4=-2/(x-1)^3（x≠1）则由x≠1知-2/(x-1)^3≠0即f'(x)...