=(x-1)^2*(x+1)^2*(x+1)
(x^2-1)^2*(x+1)
(x^4 - 2x^2+1)*(x+1)
x^5-2x^3+x+x^4 - 2x^2+1
求导得 5x^4+4x^3-6x^2-4x+1