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    Question

    If (sinθ+cosθ)/(sinθ-cosθ) = 2,

    then the value of sin4 θ is
    A 256/81 Correct Answer Incorrect Answer
    B 81/100 Correct Answer Incorrect Answer
    C 256/49 Correct Answer Incorrect Answer
    D 16/25 Correct Answer Incorrect Answer

    Solution

    (sinθ+cosθ)/(sinθ-cosθ) = 2 By applying Componendo and Dividendo (sinθ+cosθ+sinθ-cosθ)/(sinθ+cosθ-sinθ+cosθ) = (2+1)/(2-1) 2sinθ/2cosθ = 3/1 tanθ = 3/1 tanθ = Perpendicular/Base = 3/1 sin4θ = (3/√10)⁴ = 81/100

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