Question

公式法解方程，请写出过程，谢谢

公式法解方程：
x^2+x-12=0
x^2-√2x-1/4=0
x^2+4x+8=2x+11
x(x-4)=2-8x
x^2+2x=0

Answer 1

x^2+x-12=0
x1=-1/2+(1/4+12)^0.5=-1/2+(49/4)^0.5=-1/2+7/2=3
x2=-1/2-(1/4+12)^0.5=-1/2-(49/4)^0.5=-1/2-7/2=-4

x^2-√2x-1/4=0
x1=(√2)/2+(2/4+1/4)^0.5
=√2/2+(√3)/2
=(√2+√3)/2
x2=(√2)/2-(2/4+1/4)^0.5
=√2/2-(√3)/2
=(√2-√3)/2

x^2+4x+8=2x+11
x^2+2x-3=0
x1=-1+(1+3)^0.5
=-1+2
=1
x2=-1-(1+3)^0.5
=-1-2
=-3

x(x-4)=2-8x
x^2-4x=2-8x
x^2+4x-2=0
x1=-2+(4+2)^0.5
=-2+(6^0.5)
x2=-2-(4+2)^0.5
=-2-(6^0.5)

x^2+2x=0
x*(x+2)=0
x1=0
x2=-2