Question

(2х-1)+(х+2)(2х+1)=0

Решите уравнение

Answer 1

( 2x - 1 ) + ( x + 2 )( 2x + 1 ) = 0 
2x - 1 + 2x² + x + 4x + 2 = 0 
2x² + 7x + 1 = 0 
D = 49 - 8 = 41 ; √D = √ 41 
x1 = ( - 7 + √ 41 ) : 4 = - 1,75 + 0,25 √ 41 
x2 = - 1,75 - 0,25 √ 41