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Math Help - Solving a trigonometric equation

  1. #1
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    Solving a trigonometric equation

    I need help solving the following equation for all values between 0 and 360 degrees:
    sin (60 degrees - x) = 2sinx

    Normally I would set the equation to zero and factor out sin, but if I move over 2sinx it isn't possible to factor out the sin x because of the stuff in the parentheses. That's where I'm stuck.
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  2. #2
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    use the difference formula for sine on the left side ...

    \sin(a-b) = \sin{a}\cos{b} - \cos{a}\sin{b}


    btw, this one ain't pretty ...

    I it get down to \sin{x} = \pm\sqrt{\frac{3}{28}}
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  3. #3
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    Yeah, eventually I tried that and it worked. I got the same answer as you did, albeit a slightly different way.
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