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Math Help - Weird trig answer

  1. #1
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    Weird trig answer

    was not quite sure how 2 solve sin((Pi*x)/3)=0 and while looking at the answer it gave 3j and j where r the j's from

    regards Flowergirl5
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  2. #2
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    Quote Originally Posted by flowergirl5 View Post
    was not quite sure how 2 solve sin((Pi*x)/3)=0 and while looking at the answer it gave 3j and j where r the j's from

    regards Flowergirl5
    \sin{\frac{\pi x}{3}} = 0

    \frac{\pi x}{3} = \arcsin{0}

    \frac{\pi x}{3} = \pi n, where n is an integer representing the number of times you have gone around the unit circle...

    \pi x = 3\pi n

    x = 3n.


    In this case, they have just used j where I have used n.
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  3. #3
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    Actually n, or j, is the number of times you have gone halfway around the unit circle. sine is 0 at any multiple of \pi.

    (Until I saw Prove It's answer I was about to try to make "j" the imaginary unit!)
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