配方法解方程2x^2-3x+1=0
x^2-3/2x+1/2=0
x^2-3/2x+(3/4)^2-(3/4)^2+1/2=0
(x-3/4)^2=(1/4)^2
x-3/4=±1/4
x1=1/4+3/4=1
x2=-1/4+3/4=1/2