Determining system response to a superposition of sinusoids
Since the response to a LTI system to a sinusoid is so easy to characterize, a
general technique for finding the response to a more general class of input
signals is as follows. If we can decompose the inputs signal as a superpositon
of sinusoids, then we can find the response of the system to each constituent
sinusoid. By linearity, the system output is the superposition of these
individual responses.
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