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Homework Help: Angle between vectors

  1. Sep 20, 2008 #1
    A person walks in the following pattern: 6.6 km north, then 3.0 km west, and finally 7.0 km south. How far and in what direction would a bird fly in a straight line from the same starting point to the same final point?

    I found that the distance would be 3.02 km. My problem is trying to find the angle. I came up with an angle of 7.59 degrees but that was not right. Please, any help would be appreciated.
  2. jcsd
  3. Sep 20, 2008 #2
    Try using this formula: cos([tex]\alpha[/tex]) = (u(dot)v)[tex]/[/tex](|u||v|)

    Sorry I am not very good with latex but it says that the cosine of alpha is equal to the dot product of the two vectors that you need the angle between over the magnitude of of one of your vectors times the other. So with your info solve for alpha.
    If you need clarification please ask.
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