360/(x+y)+360/(x-y)=35 360/(x+y)=360+(x-y)=5 y
x+y=5; x^y+y^x=17
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
二元函数f(x,y)=x+y/x-y,求f(y/x,x/y)
) y=cos(x-y)
[x(x-y)-y(x-y)+(x+y)(x-y)]÷2x其中x=2012 y=2013
先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y
求y'=y/(y-x)
x-y / 5y= (y-x)^2 / ( )
已知:4x = 5y,求(x+y) :y
Y={X (-5
6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5
3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27