Question

Найдите х
а) 3(x-2)<8-2x
b)2x^2-5x-7<0
c)3(x-2)<8-2x и 2x^2-5x-7<0

Answer 1

Решение задания на фото.

Answer 2

$1)quad 3(x-2) textless 8-2x\\3x-6 textless 8-2x\\5x textless 14\\x textless 2,8\\2)quad 2x^2-5x-7 textless 0\\D=81; ,; ; x_1=-1; ,; ; x_2=3,5\\2(x+1)(x-3,5) textless 0; quad +++(-1)---(3,5)+++\\xin (-1;; 3,5)$

$3)quad left { {3(x-2) textless 8-2x} atop {2x^2-5x-7 textless 0}} right. ; left { {{xin(-infty ;; 2,8)} atop {xin (-1;; 3,5)}} right. ; Rightarrow ; ; xin (-1;; 2,8)$