How to use reference angles to help evaluate for an angle

The video tutorial covers the process of sketching angles, identifying reference angles, and using special right triangles to evaluate trigonometric functions like sine, cosine, and tangent. The instructor explains how to break down angles into parts, find reference angles, and use these to simplify trigonometric calculations without a calculator. The tutorial emphasizes understanding the relationships within special right triangles and applying these to solve problems efficiently.

What are the sine, cosine, and tangent values for the angle -4π/3?

How does the quadrant affect the sign of the tangent function for -4π/3?