Question

Помогите пожалуйста решить неравенство:
(√15-4)x<31-8√15

Answer 1

$(\sqrt{15}-4)x<31-8\sqrt{15}\ /:(\sqrt{15}-4)\\\\x>\frac{31-8\sqrt{15}}{\sqrt{15}-4}\\\\x>\frac{(31-8\sqrt{15})(\sqrt{15}+4)}{(\sqrt{15}-4)(\sqrt{15}+4)}\\\\x>\frac{31\sqrt{15}+124-120-32\sqrt{15}}{15-16}\\\\x>\frac{4-\sqrt{15}}{-1}\\\\x>\sqrt{15}-4\\\\x\in(\sqrt{15}-4;+\infty)$