2个方程上下相减:
x^2-y^2-根号3*(x-y)=0
(x+y)(x-y)-根号3*(x-y)=0
(x+y-根号3)(x-y)=0
x不等于y,那么x+y-根号3=0
y/x+x/y =(x^2 + y^2)/xy =(x+y)^2 - 2xy=3-2=1