Question

用配方法解方程：2x²-x-2=0.我方程很差,

Answer 1

2x²-x-2=0

x^2-x/2-1=0

x^2-x/2=1

x^2-x/2+1/16=1+1/16

(x-1/4)^2=17/16

x-1/4=±根号17/4

x=1/4±根号17/4