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MathsMediumNumerical2024 · 27 Jan Shift 1

Q81.If α satisfies the equation x2 + x + 1 = 0 and (1 + α)7 = A + Bα + Cα2, A, B, C ≥0 , then 5(3 A −2 B −C) is equal to

What This Question Tests

The question involves recognizing that 'α' is a cube root of unity and then using its properties to simplify the given expression and solve for the coefficients A, B, C.

Concepts Tested

Cube roots of unityAlgebraic manipulation of complex numbersBinomial expansion

Formulas Used

x² + x + 1 = 0 implies x = ω or ω²

1 + ω + ω² = 0

ω³ = 1

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