Question

(2х+1)(х+4)-3х(х+2)<0 

Решите неравенство 

Answer 1

(2х+1)(х+4)-3х(х+2)<0 

2x^2+9x+4-3x^2-6x<0

-x^2+3x+4<0

D=3^2-4*-1*4=25     √D=5
x1=(-3-5)/(2*-1)=4
x2=(-3+5)/(2*-1)=-1

Ответ: (-∞;-1)v(4;+∞)

Answer 2

=2х^2+8х+х+4-3х^2-6х <0

-х^2+3х+4<0