α, β are the roots of the equation x2 + 4x + 5. Find α3 + β3
4
-4
6
-6
α + β = -4
αβ = 5
(α+β)3= α3 + β3 + 3αβ(α + β)
⇒ α3 + β3 = (α+β)3 - 3αβ(α + β)
= (−4)3 - 3 × (5) × (-4)
= -64 + 60
= - 4