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Signal

Compute the Fourier series coefficients of the following signal:

$ x(t) = 3cos(7t) + 11sin(4t) $


Fourier series

$ x(t) = 3cos(7t) + 11sin(4t) $

$ x(t) = 3\frac{e^{i7t}+ e^{-i7t}}{2} + 11\frac{e^{i4t}- e^{-i4t}}{2i} $

$ x(t) = \frac{3}{2}e^{i7t}+ \frac{3}{2}e^{-i7t} + \frac{11}{2i}e^{i4t}- \frac{11}{2i}e^{-i4t} $


Coefficients

$ w_0=1 $

$ a_4= \frac{11}{2i} $

$ a_{-4}= -\frac{11}{2i} $

$ a_7=a_{-7}= \frac{3}{2} $

$ a_k = 0 $ for all other$ k \in \mathbb{Z} $

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