Questions Page - Rhea

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• Review by Jacob Holtman

There is a lot of good work but some of the data seems extra such as e^− j2πn = 1 which can be said is true only when n is an integer and not any real number. In the example it would be good to mention the sifting property for the integral of a delta. I like how the reasoning is explained for the work and why the idft is used unlike the dft.

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• Review by Andrew Pawling

Really great explanation. I like how you showed the common mistake that student make with continuous signals. The slecture could be improved with some graphical examples. I disagree and think showing e^− j2πn = 1 is helpful. It will always be true in this case since we are working in discrete time. If you didn't realize this the simplification of the sum could be confusing.

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• Review by Sahil Sanghani
  • I really liked your slecture. Showing how e ^{− j2πn} = 1 was really helpful. Also showing the common mistake students make in continuous time was useful. You really showed the necessity for the guess and check method in this derivation. Overall this was a great slecture that was easy to follow and understand.

• Review by Randall Cochran

Your slecture was really good. I liked how you showed how the wrong approach to solving the problem with the exponential would only lead to trouble. I also liked how you explained the periodicity property and added the fact about the exponential equaling 1. It could be a good refresher for someone reviewing the topic.

• Review by Hyungsuk Kim
  
  • I thought this slecture is good. Everything is well explained and very well organized in order. So I was able to get some idea on how to DTFT of complex exponential function.
    

• Review by Michael Hayashi

The material in this slecture was presented well. The note on the periodicity of the DTFT was well-written, and the caveat about $ n \in \mathcal{Z} $ for $ e^{-j2\pi n} $ to converge to 1 was absolutely necessary and explained well for this course's purposes. Similarly, citing the oscillatory nature of complex exponential functions as a way to compute the DTFT is a powerful technique to impart without resorting to mathematical notation.

• Review by Matt Miller

The material was very clearly explained, however there were some formatting issues with some of the equations.

• Review by Evan Stockrahm

Good job explaining the periodicity property and going above and beyond to explain that 1^t does not equal 1 as opposed to the fact that 1^n does equal 1. Overall, a masterful job was done creating this slecture.

• Review by student 9
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• Review by student 10
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