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Math Help - trig help please!!!

  1. #1
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    Question trig help please!!!

    Solve the equation:

    π-3arccosθ=0


    all i understand is arccosθ=0 means cos0=θ

    but i'm getting confused when there is a value multiplying arc



    the answer is arccosθ=π/3,θ=cosπ/3 =1/2
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  2. #2
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    \pi-3Cos^{-1}\theta=0

    \pi=3Cos^{-1}\theta

    \frac{\pi}{3}=Cos^{-1}\theta

    Cos^{-1}\ is\ the\ inverse\ operation\ to\ Cos

    \theta=Cos\frac{\pi}{3}
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  3. #3
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    Quote Originally Posted by ladythugette View Post
    Solve the equation:

    π-3arccosθ=0


    all i understand is arccosθ=0 means cos0=θ

    but i'm getting confused when there is a value multiplying arc



    the answer is arccosθ=π/3,θ=cosπ/3 =1/2
    this is a poorly posed equation ... the input for an inverse trig function is normally a trig ratio, not an angle, because the output of the arccos function is an angle. \theta represents an angle.

    using x instead of \theta ...

    \pi - 3\arccos{x} = 0

    \arccos{x} = \frac{\pi}{3}

    x = \cos\left(\frac{\pi}{3}\right) = \frac{1}{2}
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