Question

Сократите дробь
$\frac{a-b}{a+b} - \frac{a+b}{a}$

Answer 1

$\frac{a-b}{a+b}-\frac{a+b}{a}=\frac{a(a-b)-(a+b)^2}{a(a+b)}=\frac{a^2-ab-(a^2+2ab+b^2)}{a(a+b)}=\frac{a^2-ab-a^2-2ab-b^2}{a(a+b)}= \\ \\ =\frac{-3ab-b^2}{a(a+b)}=-\frac{b(3a+b)}{a(a+b)}$