Question

.1) (m ^ 2 - 12)/(m - 4) - 4/(m - 4) при m = - 2 2) (5k + 11)/(k ^ 2 - 9) - (4k + 14)/(k ^ 2 - 9) при k = - 2, 8 3) (3y ^ 2 - 15)/(7 - y) + (34 + 2y ^ 2)/(y - 7) ) При y = 2 4) (5m ^ 2 + 41)/(9 - 2m) - (40 - 9m ^ 2)/(2m - 9) при m = 2​

Answer 1

1)

$\frac{m {}^{2} - 12 - 4 }{m - 4} \\ \frac{m { }^{2} - 16}{m - 4} \\ \frac{(m - 4) \times (m + 4)}{m - 4} \\ m + 4 \\ - 2 + 4 = 2$

2)

$\frac{5k + 11 - (4k+ 14}{k {}^{2} - 9 } \\ \frac{5k + 11 - 4k - 14}{(k - 3) \times (k + 3)} \\ \frac{k - 3}{(k - 3) \times (k + 3) } \\ \frac{1}{k + 3} \\ \frac{1}{ - 2.8 + 3} = 5$

3)

$- \frac{ 3y {}^{2} - 15}{y - 7} + \frac{34 + 2y {}^{2} }{y - 7} \\ \frac{ - 3 {}^{2} + 15 + 34 + 2y {}^{2} }{y - 7} \\ \frac{ - y {}^{2} + 49 }{x - 7} \\ \frac{49 - y {}^{2} }{y - 7} \\ \frac{ - (y - 7) \times (7 + y)}{y - 7} \\ - (7 + y) \\ - 7 - y \\ - 7 - 2 = - 9$

4)

$- \frac{5m {}^{2} + 41}{2m - 9} - \frac{40 - 9m {}^{2} }{2m - 9} \\ - \frac{5m {}^{2} + 41 + 40 - 9m{}^{2} }{2m - 9} \\ - \frac{81 - 4m {}^{2} }{2m - 9} \\ - \frac{ - (2m- 9) \times (9 + 2m)}{2m - 9} \\ 9 + 2m \\ 9 + 2 \times 2 = 13$