Unit circle is essential for trigonometric calculations because it provides a clear and intuitive framework. 15 By plotting points on the unit circle, it is easy to visualize and compute sine and cosine values for various angles. 1

Some other benefits of using the unit circle:

• Connection between geometry and algebra. 1 It allows to connect geometric concepts, such as angles and distances, with algebraic expressions and equations, enriching understanding of both disciplines. 1
• Definition of trigonometric functions. 2 The unit circle allows to define the sine, cosine, and tangent functions for all angles, extending beyond right triangles to include any angle, including those greater than 90 degrees and negative angles. 2