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Homework Help: Trigonometry help ! !

  1. Jul 12, 2011 #1
    1. The problem statement, all variables and given/known data
    will sum1 prove this ........@=theta
    1-cos@ / sin@ = tan(@/2)

    2. Relevant equations

    3. The attempt at a solution
    i tried to do this
    cos@ = cos^2(@/2) - sin^2 (@/2)
    wat now?
    thats doesnt get me anywhere
    Last edited: Jul 12, 2011
  2. jcsd
  3. Jul 12, 2011 #2


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    Homework Helper

    Since you have a half angle on the right side, you'll want to convert all angles into their half angle equivalents. For example, [tex]\sin(2x)=2\sin(x)\cos(x)[/tex] therefore [tex]\sin(\theta)=2\sin\left(\frac{\theta}{2}\right) \cos \left(\frac{\theta}{2}\right)[/tex]
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