x三次方+x平方-5x+3=0
x^3+x^2-2x-(3x-3)=0
x(x^2+x-2)-3(x-1)=0
x(x+2)(x-1)-3(x-1)=0
(x-1)(x^2+2x-3)=0
(x-1)(x+3)(x-1)=0
所以,方程的根为：x1=x2=1,x3=-3