2x³-6x+4=0
x³-3x+2=0
显然x=1是方程的解,所以想办法分解出x-1
x³-1-3x+3=0
(x-1)(x²+x+1)-3(x-1)=0
(x-1)(x²+x+1-3)=0
(x-1)(x²+x-2)=0
(x-1)(x-1)(x+2)=0
所以x=1或x=-2