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Math Help - Double angle question help

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    Double angle question help

    The angle x lies in the interval pi/2 lessthanequal x lessthanequal pi, and sin^2 x = 8/9. Determine the value of sin 3x
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    Quote Originally Posted by Devi09 View Post
    The angle x lies in the interval pi/2 lessthanequal x lessthanequal pi, and sin^2 x = 8/9. Determine the value of sin 3x
    Note that sin(3x) = sin(2x + x) = sin(2x) cos(x) + sin(x) cos(2x)

    What are sin(2x) and cos(2x)?

    -Dan
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