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Homework Help: Trig Identity Simplification

  1. Aug 24, 2012 #1
    1. The problem statement, all variables and given/known data

    Simplify the following:

    (1/cos2θ) - (1/cot2θ)


    2. Relevant equations

    Various trig identities

    3. The attempt at a solution

    I tried to make cos2θ into 1-sin2θ and cot2θ into csc2θ-1 but still couldn't find any obvious solution. Help?
     
  2. jcsd
  3. Aug 24, 2012 #2
    What do you get if you express cot as something using sines and cosines?? What if you then add up the fractions?
     
  4. Aug 25, 2012 #3
    Did you try simply inverting both fractions? Does that show similarity to a trigonometric identity that you know?
     
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