x3-3x2+x+1=0怎么变成(x-1)(x2-2x-1)=0请尽快回答

问题描述:

x3-3x2+x+1=0怎么变成(x-1)(x2-2x-1)=0
请尽快回答

x3-2x2-x2-x+2x+1=x (x2-2x-1)-(x2-2x-1)=(x-1)(x2-2x-1)

x3-3x2+x+1=0
x3-x2-2x2+2x-x+1=0
x2(x-1)-2x(x-1)-(x-1)=0
(x-1)(x2-2x-1)=0

(x³-x²)-(x²-x)-(x²-1)=0
x²(x-1)-x(x-1)-(x+1)(x-1)=0
(x-1)(x²-x-x-1)=0
(x-1)(x²-2x-1)=0