Question

Помогите сделать номер 560

Answer 1

$frac{2}{xy} :( frac{1}{x} - frac{1}{y} )^2- frac{x^2+y^2}{(x-y)^2} = frac{2}{xy} :( frac{1}{x^2} - frac{2}{xy} + frac{1}{y^2} )- frac{x^2+y^2}{(x-y)^2} =$
$= frac{2}{xy} : frac{y^2-2xy+x^2}{x^2y^2} - frac{x^2+y^2}{(x-y)^2} = frac{2}{xy} * frac{x^2y^2}{y^2-2xy+x^2} - frac{x^2+y^2}{(x-y)^2} =$
$= frac{2xy}{(x-y)^2} - frac{x^2+y^2}{(x-y)^2} = frac{2xy-x^2-y^2}{(x-y)^2} = frac{-(x^2-2xy+y^2)}{(x-y)^2} =- frac{(x-y)^2}{(x-y)^2} =-1$