Решите неравенство (2х - 7)(2х + 7) ≥ 6х − 51.
(2x-7)(2x+7)≥6x-51
4x²-49-6x+51≥0
4x²-6x+2≥0
2x²-3x+1≥0
2x²-3x+1=0
D=9-8=1
x₁=3-1= 2/4 =1/2
4
x₂ =3+1 =1
+ - +
----------- 1/2 ----------- 1-----------
x∈(-∞; 1/2]U[1; +∞)