已知x-3y=0,且xy不等于0,求分式x^2+xy+y^2分之x^2-xy+y^2的值

已知x-3y=0,且xy不等于0,求分式x^2+xy+y^2分之x^2-xy+y^2的值
已知x-3y=0,且xy不等于0,求分式x^2+xy+y^2分之x^2-xy+y^2的值

已知x-3y=0,且xy不等于0,求分式x^2+xy+y^2分之x^2-xy+y^2的值
1/2
x=3y带入原方程
就可得