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Math Help - Trigonometry analysis

  1. #1
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    Trigonometry analysis

    please help.. pretty please?

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  2. #2
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    ONE easy trig question

    Don't mind the Alvira bit. Please explain algebraically how the diagram is in this equation: d km= 3tan((pi)x)
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  3. #3
    MHF Contributor kalagota's Avatar
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    Quote Originally Posted by delicate_tears View Post
    Don't mind the Alvira bit. Please explain algebraically how the diagram is in this equation: d km= 3tan((pi)x)
    note that on a right triangle, we have \tan\theta=\frac{b}{a} where b is the opposite side and a is the adjacent side.

    thus, from your figure, we have \tan\theta=\frac{d}{3} \Rightarrow d = 3\tan\theta..

    now, how come that \theta = \pi t?

    it was said that light spans a complete rotation (1 rev = 2\pi) every two minutes and thus the rate of revolution is \pi per minute.

    so, at time t minutes, the light spans \pi times that time t, and that is the angle of rotation, thus we have d = 3\tan(\pi t)

    aww, you were using x.. well it is just the same.. they are just dummy variables.
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  4. #4
    MHF Contributor kalagota's Avatar
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    and to answer the second part, note that tangent is not defined on \frac{\pi}{2} + n\pi..
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  5. #5
    MHF Contributor kalagota's Avatar
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    Quote Originally Posted by mr fantastic View Post
    Said where? Certainly not in this thread. Is this a continuation of a question discussed in another thread?
    yeah, actually..
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