Question

задание ниже на фото

Answer 1

Ответ:

$( \frac{5a + 2}{5a - 2} - \frac{5a - 2}{5a + 2} ) \div \frac{20a}{12 - 75 {a}^{2} } = \frac{(5a + 2)(5a + 2) - (5a - 2)(5a - 2)}{(5a - 2)(5a + 2)} \div \frac{20a}{12 - 75 {a}^{2} } = \frac{25 {a}^{2} + 20a + 4 - (25 {a}^{2} - 20a + 4)}{(5a - 2)(5a + 2)} \div \frac{20a}{12 - 75 {a}^{2} } = \frac{40a}{(5a - 2)(5a + 2)} \div \frac{20a}{3(4 - 25 {a}^{2} )} = \frac{40a \times3( 2 - 5a)(2 + 5a) }{20a(5a - 2)(5a + 2)} = \frac{2 \times 3(2 - 5a)}{5a - 2} = \frac{ - 6(5a - 2)}{5a - 2} = - 6$

Ответ: -6.