I'm asked to express the function $f(t) = \cos(4t)+\sin(6t)$ as trigonometric polynomial of the form $\sum_{n=-N}^N c_ne^{inwt}$. My first approach was to use Euler's formula to arrive at $f(t)= \frac{1}{2}e^{i4t}+\frac{1}{2}e^{-i4t}+\frac{1}{2i}e^{i6t}-\frac{1}{2i}e^{-i6t}$, but I'm not sure if this is correct and how I would turn this into a series.
2026-04-18 20:00:36.1776542436
Express $f(t) = \cos(4t)+\sin(6t)$ as trigonometric polynomial.
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