用配方法x^2-1/6x-1/3=0

题目

用配方法x^2-1/6x-1/3=0

答案

x^2-x/6-1/3=0
x^2-x/6+(1/12)^2-(1/12)^2-1/3=0
(x-1/12)^2-1/144-1/3=0
(x-1/12)^2=49/144
x-1/12=±7/12
x=1/12±7/12
x=2/3或者-1/2