The angle addition formulas for cosine and sine are:
\[
\cos(A + B) = \cos A \cos B - \sin A \sin B
\]
\[
\sin(A + B) = \sin A \cos B + \cos A \sin B
\]
So, we can rewrite $\cos(\omega t + \theta)$ and $\sin(\omega t + \theta)$ as:
\[
\cos(\omega t + \theta) =
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