Then, using the formula for cosine of a sum, we have:
$$\cos(45^\circ+30^\circ) = \cos(45^\circ)\cos(30^\circ) - \sin(45^\circ)\sin(30^\circ)$$
We can evaluate $\cos(45^\circ)$ and $\sin(45^\circ)$ using the special angles, and $\cos(30^\circ)$ and
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