把x=y+根号2代入得
2y^2 + 2根号2y + 2根号2*z^2 + 1 = 0
2[y+(根号2)/2]^2 + 2根号2*Z^2 = 0
∴y+(根号2)/2=0
2根号2*z^2=0
∴y=-(根号2)/2
z=0
x=(根号2)/2
∴x+y+z=0
把x=y+根号2代入得
2y^2 + 2根号2y + 2根号2*z^2 + 1 = 0
2[y+(根号2)/2]^2 + 2根号2*Z^2 = 0
∴y+(根号2)/2=0
2根号2*z^2=0
∴y=-(根号2)/2
z=0
x=(根号2)/2
∴x+y+z=0