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Angle between vectors

  1. Apr 1, 2010 #1
    how to find two vectors that make an angle of 60O with v=<3,4>??

    can i let b=<x,y>, then

    cos60=(3x+4y)/5sqrt(x2+y2)

    5sqrt(x2+y2)=3x+4y
     
  2. jcsd
  3. Apr 1, 2010 #2

    tiny-tim

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    Welcome to PF!

    Hi hazellaw! Welcome to PF! :smile:

    (have a square-root: √ and a degree: º :wink:)
    That'll certainly do it. :smile:

    But easier would be

    i] use <cosθ,sinθ> instead of <x.y>

    or ii] write <3,4> in polar form (r,θ)

    or iii] find the line perpendicular to <3,4>, and go along it the appropriate distance. :wink:
     
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