(x/x-y + x^2+y^2/y^2-x^2 + x/x+y) * (2/x+y)^2

1)(x(-x-y)+x²+y²+x(x-y))/(y²-x²)=(-x²-xy+x²+y²+x²-xy)/(y²-x²)=(y²-2xy+x²)/(y²-x²)=                (y-x)²/(y-x)(y+x)=(y-x)/(y+x) 2)(y-x)/(y+x)*4/(x+y)²=4(y-x)/([x+y)³