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Sine and cosine

  1. Apr 30, 2006 #1
    Hello, could anyone help me calculate the value of x?

    246.25 sin x - 676.58 cos x = -27768.42

    Thank you..

  2. jcsd
  3. Apr 30, 2006 #2


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    Gold Member

    You know the smallest value sin x can have, and the largest value cos x can have. So what is the smallest value 246.25 sin x - 676.58 cos x can have?

    (Or are you expected to work with complex numbers?)
  4. Apr 30, 2006 #3
    Ah, yea that's right. it's impossible to solve it.

    Well, this equation is derived from somewhere else, and I might have done mistake in doing it.

    This is the question:

    Use Cartesian vector method to solve the problem. If you use any other method, you will receive zero.

    A pilot wishes to fly form city A to city B, a distance of 720 km on a bearing of 70 degree. The speed of the plane is 700 km/h. An 60 km/h wind is blowing on a bearing of 110 degree. What heading should the pilot take to reach his or her destination? How long will the trip take?

    Could you help me with this please? I will post my work in 5 minutes.
    Last edited: Apr 30, 2006
  5. Apr 30, 2006 #4
    OK, here is my work:

    http://i66.photobucket.com/albums/h242/jferdina/Bearing.jpg" [Broken]
    http://i66.photobucket.com/albums/h242/jferdina/Bearing-continued.jpg" [Broken]
    Last edited by a moderator: May 2, 2017
  6. Apr 30, 2006 #5


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    As I see it, the last line is wrong, you divided the LSH by 700 but forgot to divide the RHS by 700. :)
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