解
x³-2x²+1=0
x³-x²-x²+1=0
x²(x-1)-(x²-1)=0
x²(x-1)-(x-1)(x+1)=0
(x-1)(x²-x-1)=0
∴x-1=0或x²-x-1=0
∴x=1或x=(1+√5)/2或x=(1-√5)/2