X^3 —3X+2 =X(X^2-3)+2=X(X^2-1-2)+2=X(X+1)(X-1)-2X+2=X(X+1)(X-1)-2(X-1)=(X-1)(X^2+X-2) =(X-1)(X-1)(X+2)=(X+2)(X-1)^2
=x(x^2+2x+1)-2x^2-4x+2=x(x+1)^2-2(x^2+2x+2)+6
x^3-3x+2=(x-1)(x^2+x-2)=(x-1)(x+2)(x-1)=(x+2)(x-1)^2
厄......没看懂这是啥