# Ch 14: The Unit Circle

Let our video lessons and quizzes help you become familiar with the unit circle, or a circle with a radius of one. Learn about the mathematical relationships shared by the circle and trigonometric functions.

## The Unit Circle - Chapter Summary

The purpose of this chapter is to teach you how to analyze the relationships shared by the coordinate plane, circular functions and trigonometric functions associated with the unit circle. The instructor will begin with an introduction to the most widely recognized trigonometric functions, including sines, cosines and tangents. You'll also learn how sine and cosine function on the unit circle.

A key section of the lesson covers the importance of the first quadrant of the unit circle, a uniquely patterned area and the only part of the unit where angles can be used to determine the trigonometric values for all of the functions. As the lesson continues, you'll also find out how to convert between a radian, or unit of measure for an angle, and degrees. When you finish the chapter, you should:

• Have memorized the first quadrant of the unit circle, including degrees, points and radian measures
• Understand the unit circle outside of the first quadrant
• Understand the relationships between special triangles and the unit circle
• Have practiced using the unit circle

Our video lesson on the unit circle is taught by an experienced professional with an in-depth knowledge of the subject. Each brief and engaging video is composed of easy-to-understand explanations and illustrations and is supported by a lesson transcript. Additional features include links to text-based tutorials that provide more information about key concepts and terms. At the end of the chapter, you can use the video tags to revisit important parts of the lesson and take the online self-assessment quiz to see how well you understood the presentation.

5 Lessons in Chapter 14: The Unit Circle
Test your knowledge with a 30-question chapter practice test
Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

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