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Very Basic Fourier Transform Equation

  1. Mar 15, 2016 #1
    1. The problem statement, all variables and given/known data
    So well, in class we were shown this equation for the fourier transform:
    http://puu.sh/nHsWo/042d1d01ba.png [Broken]
    First equation turns a function of time into frequency(notice theres no - in the exponent of e)
    Second one does the opposite(notice there is a - in the exponent of e)

    I searched online and found this video:

    3f6aa20cac.jpg

    the first equation on the left transforms function of time into frequency but there is a - this time why so?
    arent they meant to be the same

    2. Relevant equations


    3. The attempt at a solution
     
    Last edited by a moderator: May 7, 2017
  2. jcsd
  3. Mar 15, 2016 #2

    BvU

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    It's just the sign of f. The video definition is more sensible. Can you guess why I say that ?
     
  4. Mar 15, 2016 #3
    Brian Douglas's videos are great.

    He is the only reason why I passed Modern Control Systems. I'd watch the videos and understand the material. Prof was useless.
     
  5. Mar 16, 2016 #4

    rude man

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    I think the formula you were given in class is wrong. Even if it works it's completely at variance with every other transform pair I've ever encountered, and I've encountered many.
     
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