Question

Помогите с 28 заданием,пожалуйста

Answer 1

1)
$frac{a}{b} - 1 = frac{a}{b} - frac{b}{b} = frac{a - b}{b}$
2)
$frac{8}{ {x}^{2} } - frac{3}{x} + 2 = frac{8}{ {x}^{2} } - frac{3x}{ {x}^{2} } + frac{2 {x}^{2} }{ {x}^{2} } = frac{8 - 3x + 2 {x}^{2} }{ {x}^{2} }$
3)
$5 - frac{4m + 5n}{n} = frac{5n}{n} - frac{4m + 5n}{n} = frac{5n - (4m + 5n)}{n} = frac{5n - 4m - 5n}{n} = - frac{4m}{n}$
4)
$frac{4c + 3}{c - 1} - 3 = frac{4c + 3}{c - 1} - frac{3(c - 1)}{c - 1} = frac{4c + 3 - 3(c - 1)}{c - 1} = frac{4c + 3 - 3c + 3}{c - 1} = frac{c + 6}{c - 1}$
5)
$frac{ {a}^{2} + {b}^{2} }{2a - b} + 2a + b = frac{ {a}^{2} + {b}^{2} }{2a - b} + frac{(2a + b)(2a - b)}{2a - b} = frac{ {a}^{2} + {b}^{2} }{2a - b} + frac{4 {a}^{2} - {b}^{2} }{2a - b} = frac{ {a}^{2} + {b}^{2} + 4 {a}^{2} - {b}^{2} }{2a - b} = frac{5 {a}^{2} }{2a - b}$
6)
$m - frac{25}{m - 5} - 5 = m - 5 - frac{25}{m - 5} = frac{ {(m - 5)}^{2} }{m - 5} - frac{25}{m - 5} = frac{ {(m - 5)}^{2} - 25}{m - 5} = frac{ {m}^{2} - 10m + 25 - 25 }{m - 5} = frac{ {m}^{2} - 10m}{m - 5}$