Question

спростить дроби дам 45 баллов баллов!!!​

Answer 1

$1) \frac{2}{34} + \frac{4}{3a} - \frac{6 - a {}^{2} }{3a} = \frac{1}{17} + \frac{4}{3a} - \frac{6 - a {}^{2} }{3a} = \frac{3a + 68 - 17(6 - a {}^{2}) }{51a} = \frac{3a + 68 - 102 + 17a {}^{2} }{51a} = \frac{3a - 34 + 17a {}^{2} }{51a } = \frac{17a {}^{2} + 3a - 34 }{51a}$

$2) \frac{2a + 3}{5b} + \frac{2a - 9}{5b} + \frac{a + 1}{5b} = \frac{2a + 3 + 2a - 9 + a + 1}{5b} = \frac{5a - 5}{5b} = \frac{5(a - 1)}{5b} = \frac{a - 1}{b}$

$3) \frac{ {x}^{2} }{x + 1} + \frac{2x - 1}{x + 1} + \frac{1 - x}{x + 1} = \frac{x {}^{2} + 2x - 1 + 1 - x}{x + 1} = \frac{x {}^{2} + x }{x + 1} = \frac{x \times (x + 1)}{x + 1} = x$

$4) \frac{(m + n)}{m - n} - \frac{m}{m - n} - \frac{m}{m - n} = \frac{m + n}{m - n} - 2 \times \frac{m}{m - n} = \frac{m + n}{m - n} - \frac{2m}{m - n} = \frac{m + n - 2m}{m - n} = \frac{ - m + n}{m - n} = \frac{ - (m + n)}{m - n} = - 1$

$5) \frac{1}{a - c} + \frac{1}{c - a} = \frac{1}{a - c} + \frac{1}{ - (a - c)} = \frac{1}{a - c} - \frac{1}{a - c} = 0$