解方程X的三次方减去X的二次方的二倍再加一等于零
问题描述：
解方程X的三次方减去X的二次方的二倍再加一等于零
答
x^3-2x^2+1=0
(x-1)(x^2-x-1)=0
x-1=0即x=1或x^2-x-1=0
x^2-x-1=0
(x-1/2)^2=5/4
x-1/2=±√5/2
x=(1+√5)/2或x=(1-√5)/2
综上x=1或x=(1+√5)/2或x=(1-√5)/2