Question

решите пожалуйста предел

Answer 1

2x² - 9x - 5 = (2x + 1)(x - 5)

D = 81 + 40 = 121

x12 = (9 +- 11)/4 = 5   -1/2

x² - 25 = (x - 5)(x + 5)

(2x² - 9x - 5)/(x² - 25) = (x - 5)(2x + 1)/((x - 5)(x + 5)) = (2x + 1)/(x + 5)

1. lim (5) = (2*5 + 1)/(5 + 5) = 11/10

2. lim (∞) = lim (∞) (2x + 1)/(x + 5) ={делим на х}   lim (∞) (2 + 1/x)/(1 + 5/x) = (2 + 0)/(1 + 0) = 2