x^2+3x+1=0x^2+3x+9/4=5/4(x+3/2)^2=5/4 x1=(-3+根号5)/2x2=(-3-根号5)/2 祝你学习进步！
x^2+3x+1=0x^2+3x+9/4=5/4(x+3/2)^2=5/4
2(x^2+3x+1)=0x1,2=[-3加减根号(5)]/2
2x^2+6x+2=0 x^2+3x+1=0x1=(-3+根号5)/2x2=(-3-根号5)/2
