Find the reference angle and sketch both angles in standard position

The video tutorial explains how to find the reference angle for a given negative angle. It begins by defining the reference angle and sketching the angle in standard position. The tutorial then addresses the challenge of using negative angles and introduces the concept of coterminal angles to find a positive equivalent. By adding 360 degrees to the negative angle, a positive coterminal angle is obtained, which is then used to calculate the reference angle. The process is demonstrated with an example, showing how to apply the formula for the third quadrant to find the reference angle.

How do you determine the acute angle between the terminal side of an angle and the horizontal axis?

What formula is used to find the reference angle in the third quadrant?