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Math Help - sin rule

  1. #1
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    Cool sin rule

    find 4 solutions of the equation
    (sinx)2 = 1/4 for x between 0degrees and 360degrees..
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  2. #2
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    Quote Originally Posted by hi00000 View Post
    find 4 solutions of the equation
    (sinx)2 = 1/4 for x between 0degrees and 360degrees..
    This isn't a sine rule question... but I'll solve it...

    \sin^2{x} = \frac{1}{4}

    \sin{x} = \pm \frac{1}{2}

    So we need to figure out which x satisfy this equation.


    The focus angle is 30^{\circ}.

    In each of the other quadrants, the angles that satisfy this equation are

    180^{\circ} - 30^{\circ}, 180^{\circ} + 30^{\circ}, 360^{\circ} - 30^{\circ}.


    So the four angles are \left\{30^{\circ}, 150^{\circ}, 210^{\circ}, 330^{\circ}\right\}.
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  3. #3
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    i'mm yaaa.......??//
    anyways thanx 4 that
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  4. #4
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    Quote Originally Posted by hi00000 View Post
    find 4 solutions of the equation
    (sinx)2 = 1/4 for x between 0degrees and 360degrees..
    \sin^2x=\sin^2\frac\pi{6}

    x=n\pi\pm\frac\pi{6}

    For n=0\ ,\ x=30
    For n=1\ ,\ x=210\ or\ x= 150
    For n=2\ ,\ x=330
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