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Solve (cos² x - sin² x) / (cos² x + sin x cos x) = 1 - tan x?

using identities

tanx = sinx/cosx andd

cos^2 x + sin^2 x = 1

1 Answer

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  • 9 years ago
    Favorite Answer

    The given problem is to prove the identity, not to solve

    (cos² x - sin² x) / (cos² x + sin x cos x)

    = ( cos x + sin x)(cos x - sin x) / cos x( cos x + sin x)

    = (cos x - sin x) / cos x

    = ( cos x / cos x ) - ( sin x / cos x )

    = 1 - tan x

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