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Math Help - Find trig identities of an angle

  1. #1
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    Exclamation Find trig identities of an angle

    find sin, cosine, and the tangent of the angle 11pi/12
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    Quote Originally Posted by jumpman23 View Post
    find sin, cosine, and the tangent of the angle 11pi/12
    \frac{11\pi}{12} is half of \frac{11\pi}{6} ... use your half-angle identities.
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    Or, as an alternative, note that \frac{11\pi}{12}=\frac{3\pi}4+\frac\pi6.
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  4. #4
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    sin(11pi/12) = sin(pi - 11pi/12) = sin(pi/12)
    = sin( pi/3 - pi/4)
    = 1/sqrt(2)[ sqrt(3) - 1 ] = [ sqrt(6) - sqrt(2) ]/ 2
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