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    by first writing [email protected] as sin([email protected] [email protected]), express [email protected] in terms of [email protected]
    Hence solve the equation [email protected] [email protected] 0<[email protected]<=360 degrees


    @ = thetre
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    (Original post by uzer)
    by first writing [email protected] as sin([email protected] [email protected]), express [email protected] in terms of [email protected]
    Hence solve the equation [email protected] [email protected] 0<[email protected]<=360 degrees


    @ = thetre
    *theta. It might be beneficial to learn some basic LaTex, there's a guide here:
    http://www.thestudentroom.co.uk/wiki/LaTeX
    How many of these are you actually getting out? Did you get the last one out?


    Use the sine double angle formula for A = 2\theta, B = \theta, then use the double angle formulae again.
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    yes dont worry i have done all the sums so far

    i have tried double angle foormula no luck
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    (Original post by uzer)
    yes dont worry i have done all the sums so far

    i have tried double angle foormula no luck
    I was getting a little worried. If you're getting them out that's fine.

    \sin(A+B) = \sin A \cos B + \cos A \sin B

    \therefore \sin(2\theta + \theta) = \sin 2\theta \cos \theta + \cos 2\theta \sin \theta
    \therefore \sin 3\theta = (2\sin\theta\cos\theta)\cos\thet  a + (\cos^2 \theta - \sin^2 \theta)\sin \theta

    Then you expand and use \cos^2 \theta + \sin^2 \theta = 1.
 
 
 
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Updated: January 25, 2015
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