y'=(x^3-3x^2)·(x-1)^(-3)y''=(3x^2-6x)·(x-1)^(-3)-3(x^3-3x^2)·(x-1)^(-4)=3x·(x-1)^(-4)·[(x-2)(x-1)-(x^2-3x)]=3x·(x-1)^(-4)·2=6x·(x-1)^(-4)
