Question

2x的平方-x-1=0 (用配方法)

Answer 1

2 x^2 - x + 1/8 -1-1/8=0

(x-1/4)^2=9/16

x-1/4=+-3/4

x=1/4+-3/4

x=1,x=-1/2

x²-4x-32=0

(x-8)(x+4)=0

x= 8 或者 x= -4