How to find the reference angle of a negative radian

The video tutorial explains the concept of negative angles and radians, focusing on how to measure and understand them. It guides viewers through the process of finding the reference angle to the X axis and calculating Theta prime. The tutorial emphasizes the importance of acute reference angles being positive and provides a step-by-step calculation, including rounding to approximate values.

Explain the concept of acute reference angles and their properties.

What is the rounded value of the reference angle discussed in the text?