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Question:

If α and β are the roots of the quadratic equation, x² + x sinθ - 2sinθ = 0, θ∈(0, π/2), then α¹² + β¹²(α⁻¹² + β⁻¹²) (α - β)²⁴ is equal to:

2⁶(sinθ + 8)¹²

2¹²(sinθ - 8)⁶

2¹²(sinθ - 4)¹²

2¹²(sinθ + 8)¹²

Solution:

Correct option is D. 2¹²(sinθ + 8)¹²
α¹² + β¹²(1/α¹² + 1/β¹²) (α - β)²⁴ = (αβ)¹²(α - β)²⁴ = (αβ)¹²[(α + β)² - 4αβ]¹² = [αβ(α + β)² - 4αβ]¹² = (-2sinθ(sin²θ + 8sinθ))¹² = 2¹²(sinθ + 8)¹²