Question

СРОЧНО! Задания на картинках!

Answer 1

$\frac{ {x}^{2} - 4}{5x - 10} - \frac{ {x + 4x + 4} }{5x + 10} = \\ = \frac{(x - 2)(x + 2)}{5(x - 2)} - \frac{{(x + 2)}^{2} }{5(x + 2) } = \\ = \frac{x + 2 - (x + 2)}{5} = 0$
$\frac{1}{ {(a - 3)}^{2} } - \frac{2}{ {a}^{2} - 9} + \frac{1}{(a + 3) ^{2} } = \\ = ( \frac{1}{a - 3} ) ^{2} - 2 \times \frac{1}{(a - 3)} \times \frac{1}{(a + 3)} + \\ + ( \frac{1}{a + 3} ) ^{2} = {( \frac{1}{a - 3} - \frac{1}{a + 3})}^{2} = \\ = {( \frac{a + 3 - (a - 3)}{ {a}^{2} - 9} )}^{2} = \\ = \frac{ {6}^{2} }{ ({a}^{2} - 9) ^{2} } = \frac{36}{ ({a}^{2} - 9) ^{2} }$