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    Hi!!!
    I've got the question:
    Express cos^5(θ)*sin^2(θ) in terms of cosines of multiples of θ

    I'm a bit confused but I got the answer (1/32)cos7θ+(1/8)cos5θ+(5/32)cos3θ-(5/16)cosθ.
    Any help if I'm wrong pls ????
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    (Original post by ltbitters)
    Hi!!!
    I've got the question:
    Express cos^5(θ)*sin^2(θ) in terms of cosines of multiples of θ

    I'm a bit confused but I got the answer (1/32)cos7θ+(1/8)cos5θ+(5/32)cos3θ-(5/16)cosθ.
    Any help if I'm wrong pls ????
    Well you can easily verify by plugging in \theta = \frac{\pi}{2} for example.
    If you're wrong, remember that your question is the same as \cos^5(\theta)-\cos^7(\theta)
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    (Original post by RDKGames)
    Well you can easily verify by plugging in \theta = \frac{\pi}{2} for example.
    If you're wrong, remember that your question is the same as \cos^5(\theta)-\cos^7(\theta)
    ahhh welp i was wrong :laugh:
    time to try ur second suggestion lmao !!! thank you
 
 
 
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