∫(1-x)^2/x^3 dx
=∫(1-2x-x^2）/x^3 dx
=∫(x^(-3)-2x^(-2)+x^(-1)) dx
=1/(-3+1)x^(-3+1)-1/(-2+1)x^(-2+1)+ln|x|+c
=-1/(2x^2)+1/x+ln|x|+c