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Practice Problem on Discrete-time Fourier transform computation

Compute the discrete-time Fourier transform of the following signal:

$ x[n]= \sin \left( \frac{2 \pi }{100} n \right) $

(Write enough intermediate steps to fully justify your answer.)


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Answer 1

$ x[n]=\sin \left( \frac{2pi}{100} \right) $


$ x[n] = \frac{1}{2j} e^(j2 \pi/100n)-e(-j2 \pi/100n)) $

$ X_(\omega) = \sum_{n=-\infty}^{+\infty} x[n] e^{-j\omega n} $

$ X_(\omega) = \sum_{n=-\infty}^{+\infty} e^{-j2 \pi /100 n} e^{-j\omega n} $

Answer 2

Write it here.

Answer 3

We can set the $ x[n]=\sin \left( frac{2\pi} \100 \right) $


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