Question

помогите пожалуйста ​

Answer 1

$\frac{x-y}{x+y} -\frac{x+y}{x-y} =\frac{(x-y)^2-(x+y)^2}{(x+y)(x-y)} =\frac{x^2-2xy+y^2-(x^2+2xy+y^2)}{(x+y)(x-y)} =\frac{x^2-2xy+y^2-x^2-2xy-y^2}{(x+y)(x-y)} =\frac{-4xy}{x^2-y^2} \\Otvet: D$