x/(x-1)(x-2)(x-3)
=x^2/{[x*(x-3)]*[(x-1)(x-2)]}
=2x^2*{1/[x*(x-3)]-1/[(x-1)(x-2)]
=2x/(x-3)+2x^2*[1/(x-1)-1/(x-2)]
你能明白,赞同