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Math Help - Trig equations

  1. #1
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    Trig equations

    Can someone help me solve this:
    2 + cos(x) = 2sin^2(x)
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  2. #2
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    Re: Trig equations

    Rewrite it as \displaystyle 2 + \cos{(x)} = 2\left[ 1 - \cos^2{(x)} \right], expand everything, move to one side and solve the resulting quadratic equation.
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  3. #3
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    Re: Trig equations

    Thank you, i didnt think about using the pythagorean identity there
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  4. #4
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    Re: Trig equations

    Generally, trigonometric equations with powers are only possible to be solved if you can get it the equation to be only of a single trigonometric function (in this case, the cosine function).
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  5. #5
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    Re: Trig equations

    Yeah, i know all of my problems have two trig functions but i have a hard time getting them to only one
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