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Math Help - Which identity to change when solving an equation like this

  1. #1
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    Which identity to change when solving an equation like this

    Hi
    Where would you start?

    I am trying to get to one trig function and used a few different identities but am going round in circles!
    I though to express them all as cosine...then sine and I have just ended up going back on myself
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  2. #2
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    Hi

    \frac{2}{\cos(2x)}-\frac{\cos(2x)}{\sin(2x)} = \frac{\sin(2x)}{\cos(2x)}

    \frac{2\:\sin(2x)-\cos^2(2x)-\sin^2(2x)}{\cos(2x)\:\sin(2x)} = 0

    \frac{2\:\sin(2x)-1}{\cos(2x)\:\sin(2x)} =  0
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  3. #3
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    Thanks
    So that would leave me to solve arscin .05 and then divide all answers by two in the given range?
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  4. #4
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    Yes
    It leads to x=\frac{\pi}{12} [\pi] or x=\frac{5\pi}{12} [\pi]
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  5. #5
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    Brilliant
    Thanks!
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