Very Basic Fourier Transform Equation

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Discussion Overview

The discussion revolves around the Fourier transform equations presented in a class setting, specifically addressing the differences in the signs of the exponentials in the equations for transforming functions of time to frequency and vice versa. Participants explore the implications of these differences and their consistency with other definitions found online.

Discussion Character

  • Homework-related, Debate/contested

Main Points Raised

  • One participant notes that the class equation for the Fourier transform lacks a negative sign in the exponent when transforming time to frequency, questioning its correctness compared to other sources.
  • Another participant suggests that the definition provided in a video is more sensible, implying that the sign of f is the key difference.
  • A third participant expresses a positive opinion about the video creator, indicating that their content was instrumental in their understanding of related material.
  • One participant challenges the class formula, stating it is inconsistent with other transform pairs they have encountered, suggesting a potential error in the class material.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the correctness of the class equation, with some supporting the video definition and others questioning the class material. Multiple competing views remain regarding the validity of the equations presented.

Contextual Notes

There are unresolved questions about the assumptions behind the definitions of the Fourier transform and the context in which they are applied, as well as potential discrepancies in the presentation of the equations.

DiamondV
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Homework Statement


So well, in class we were shown this equation for the Fourier transform:
http://puu.sh/nHsWo/042d1d01ba.png
First equation turns a function of time into frequency(notice there's 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

Homework Equations

The Attempt at a Solution

 
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It's just the sign of f. The video definition is more sensible. Can you guess why I say that ?
 
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.
 
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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