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Homework Help: Projectile Motion and the Range Formula

  1. Feb 27, 2010 #1
    Hey Guys

    Im wondering if anyone could help me simplify the range formula for projectile motion. So far ive got R=2v^2 sin(theta) cos(theta)/g.

    Help will be appreciated. Thanks
     
  2. jcsd
  3. Feb 27, 2010 #2

    ideasrule

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    Have you seen the identity sin(2x)=2sinxcosx?
     
  4. Feb 27, 2010 #3
    No i havent
     
  5. Feb 27, 2010 #4

    ideasrule

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    Homework Helper

    Using that identity, you can simplify the range formula easily.

    Note that the identity can be derived from sin(a+b)=sin(a)cos(b)+sin(b)cos(a). Set a=b and you get sin(2a)=sin(a)cos(a)+sin(a)cos(a)=2sin(a)cos(a)
     
  6. Feb 27, 2010 #5
    so then the formula simplifies down to
    R= v^2 sin(2x)/g ?
     
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