已知x^2-3y^2=2xy(x>0,y>0),求代数式x+2y/x-y
问题描述:
已知x^2-3y^2=2xy(x>0,y>0),求代数式x+2y/x-y
答
∵x^2-3y^2=2xy∴ x^2-2xy-3y^2=0∴(x+y)(x-3y)=0∵x>0,y>0∴x-3y=0∴x=3y∴x+2y/x-y =3y+2y/3y-y=2y+2/3或=2/3(x+1)如果你的公式为:(x+2y)/(x-y)的话,则结果如下:(x+2y)/(x-y)=(3y+2y)/(3y-y)=5y...