Question

#2.1. Решите и объясните подробно

Answer 1

(1/х²+1/у²)*1/(х²+у²) = (1/х²+1/у²)/(х²+у²).

Answer 2

$\displaystyle\tt (x^{-2}+y^{-2})(x^2+y^2){-1}=\bigg(\frac{1}{x^2}+ \frac{1}{y^2}\bigg)\cdot\frac{1}{x^2+y^2}=\frac{y^2+x^2}{x^2y^2}\cdot\frac{1}{x^2+y^2}=\frac{1}{x^2y^2}$