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No solution?

  1. Nov 20, 2005 #1


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    Ive been trying to prove this identity for the past hour, and I cant seem to do it. Im starting to think its not possible. Heres the identity.
    sin2x/1-cos2x = cotx
    Can anyone give me some kind of hint. :frown:
  2. jcsd
  3. Nov 20, 2005 #2


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    First of all, learn to write your formulas PROPERLY! :grumpy:
    There is a vast difference between sin(2x)/1-cos(2x) and sin(2x)/(1-cos(2x)).
    The last one is the expression you should have used.

    To derive the identity, recall the double angle formulas.
  4. Nov 22, 2005 #3
    Substitute the formula 2cos^x - 1 for cos2x and 2sinxcosx for sin2x. then you just straight away ge the answer.
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