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Homework Help: Find energy of signal

  1. Aug 18, 2010 #1
    1. The problem statement, all variables and given/known data

    x(t) = e(-2t) * u(t)

    Ex = x2(t) dt

    Attached is the work I have done. Got stuck towards the end.

    Attached Files:

    • #2.bmp
      File size:
      285 KB
  2. jcsd
  3. Aug 19, 2010 #2
    [tex](e^{-2x})^2 = e^{-2x}e^{-2x}=e^{-2x-2x}=e^{-4x}[/tex]
    or you can use the power property associated with exponents and instantly say
    I'm assuming the exponential being squared is what messed you up, and I'm assuming you can take it from here.
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