Pre-Calculus - Using the difference of angles for cosine to evaluate for an angle cos(225-30)

The video tutorial explains how to find the cosine of the difference between two angles, 225 degrees and 30 degrees, using the cosine difference formula. It involves evaluating the cosine and sine of each angle using the unit circle, then applying these values to the formula. The tutorial concludes with simplifying the expression to find the final result.

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