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.

Example: continuous-time differentiator

Up to Systems and Linearity