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Calculating <cos^2(theta)>

  1. Jan 26, 2012 #1
    What is the expectation value of cosine squared, namely <cos^2(t)>?
  2. jcsd
  3. Jan 26, 2012 #2
    cos2x = (1+cos(2x))/2

    Integration leads to 0,5 (averaged over the lenght)
  4. Jan 26, 2012 #3


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    Science Advisor

    Another approach: cos2(x) + sin2(x) = 1. Both terms have the same average, so the average for cos2(x) = 1/2.
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