3x² - 2x - 5 > 0 D = b²-4ac = 4+60 = 64
x₁ = (-b+√D)/2a = (2+8):6 = 1 2/3
x₂ = (-b -√D)/2a = (2-8):6 = -1
3x² - 2x - 5 = (3x-5)(x+1)
(3x-5)(x+1) > 0
{ 3x - 5 > 0 { 3x - 5 < 0
{ x + 1 > 0 { x + 1 < 0
x > 1 2/3 x < 1 2/3
x > -1 x < -1
(1 2/3; ∞) (-∞; -1)
Ответ: x∈(-∞; -1)∪(1 2/3; ∞)