Question

跪求用配方法解一元二次方程的例题,

Answer 1

2x^2 - 3x - 2=0

2[x^2 - (3/2)x] - 2=0

2[x^2 - (3/2)x + (3/4)^2 - (3/4)^2] - 2=0

2[x - (3/4)]^2 - 18/16 - 2=0

2[x - (3/4)]^2 - 50/16=0

2[x - (3/4)]^2=50/16

[x - (3/4)]^2=25/16

x - (3/4)=±5/4

x - (3/4)=5/4或x - (3/4)=-5/4

x=2或x=-1/2