Question

Решите по действиям срочно надо
Заранее спасибо

Answer 1

$\frac{3a}{a - 3} + \frac{a + 5}{6 - 2a} \times \frac{54}{5a + {a}^{2} } = \frac{3a}{a - 3} + \frac{a + 5}{2(3 - a)} \times \frac{54}{a(5 + a) } = \frac{3a}{a - 3} + \frac{27}{a(3 - a)} = \frac{3a}{a - 3} - \frac{27}{a(a - 3)} = \frac{3 {a}^{2} - 27 }{a(a - 3)} = \frac{3(a - 3)(a + 3)}{a(a - 3)} = \frac{3a + 9}{a}$
$( \frac{a + 4}{a - 4} - \frac{a - 4}{a + 4} ) \div \frac{48a}{16 - {a}^{2} } = \frac{ {(a + 4)}^{2} - {(a - 4)}^{2} }{(a - 4)(a + 4)} \times \frac{16 - {a}^{2} }{48a} = \frac{ - 16a}{16 - {a}^{2} } \times \frac{16 - {a}^{2} }{48a} = - \frac{1}{3}$