x^3-3x^2+2=0
x^3-3x^2+2
=x^3-x^2-2x^2+2
=x^2(x-1)-2(x^2-1)
=x^2(x-1)-2(x-1)(x+1)
=(x-1)(x^2-2x-2)=0
x-1=0,x^2-2x-2=0
x=1,1+根号3,1-根号3