Question

Решите пожалуйста
(x⁻¹-y⁻¹)(x-y)⁻¹

Answer 1

(x⁻¹-y⁻¹)*(x-y)⁻¹=
$=( frac{1}{x} - frac{1}{y} )* frac{1}{x-y} = frac{y-x}{xy}* frac{1}{x-y} =- frac{1}{xy}$