若3x-2y=0,求(x+y)/(x-y)+(x-y)/(x+y)的值

3x-2y=0
3x=2y
x=2/3y

所以(x+y)/(x-y)+(x-y)/(x+y)
=(2/3y+y)/(2/3y-y)+(2/3y-y)/(2/3y+y)
=-(5/3y)/(1/3y)-(1/3y)/(5/3y)
=-5-1/5
=-26/5

3x-2y=0 得y=1.5x
(x+y)/(x-y)+(x-y)/(x+y)=2.5x/-0.5x+(-0.5x)/2.5x
=-5-0.2
=-5.2

x=2y/3
代入公式
(2y/3+y)/(2y/3-y)+(2y/3-y)/(2y/3+y)
=(2/3+1)/(2/3-1)+(2/3-1)/(2/3+1)
=(-5)+(-1/5)
=-26/5

由题意可以设x=2t y=3t t is not 0;
则打入，消去t 原式=5/(-1) +(-1)/5 = -26/5
谢谢

3x=2y,原式=(x+3/2x)/(x-3/2x)+(x-3/2x)(x+3/2x)=-26/5