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The Fourier Transform

  1. Aug 22, 2006 #1
    Hello everyone ^^

    Why I can say "The Fourier transform tells us " how much sinusoid" there is in the waveform at a given frequency "w""

    Form Linear circuit analysis by Artice M. David

    thanks a lot
  2. jcsd
  3. Aug 22, 2006 #2


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    It is meant in the following sense...

    if you take the Fourier transform of a function F(x), the result is a function A(w), right?


    Well it turns out that this function A(w) is such that


    i.e. A(w) is the amplitude of the sine wave [itex]e^{iwx}[/itex] of frequency w. So the bigger A is for a given w, the bigger the contribution of this sine wave in the integral making up F(x).

    You must think in terms of analogy with Fourier series.
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