How to evaluate the difference of two angles for tangent, tan

The video tutorial explains how to evaluate the tangent of 165 degrees by rewriting it as the difference of tangents of 210 and 45 degrees. The instructor provides a formula for tangent difference and demonstrates how to plug in angles and simplify the expression. The tutorial covers evaluating tangent using sine and cosine coordinates, rationalizing denominators, and multiplying by the conjugate to simplify expressions. The final result is a simplified exact answer for the tangent of 165 degrees.

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