Решение
3x⁴ - 2x² - 16 = 0
Пусть x² = y, тогда
3y² - 2y - 16 = 0
D = 2² + 4*3*16 = 196
y₁ = (2 - 14)/6
y₁ = - 2
y₂ = (2 + 14)/6
y₂ = 16/6
y₂ = 2(2/3)
x² = - 2 не имеет смысла
x² = (8/3)
x₁ = -√(8/3)
x₁ = - 2√(2/3)
x₁ = - 2√6 / 3
x₂ = √(8/3)
x₂ = 2√(2/3)
x₂ = 2√6 / 3