# Ch 20: Using Trigonometric Functions: Help and Review

The Using Trigonometric Functions chapter of this High School Precalculus Help and Review course is the simplest way to master trig functions. This chapter uses simple and fun videos that are about five minutes long, plus lesson quizzes and a chapter exam to ensure students learn the essentials of using trigonometric functions.

## Who's it for?

Anyone who needs help learning or mastering high school precalculus material will benefit from taking this course. There is no faster or easier way to learn high school precalculus. Among those who would benefit are:

• Students who have fallen behind in understanding trig functions or working with the double angle formula.
• Students who struggle with learning disabilities or learning differences, including autism and ADHD
• Students who prefer multiple ways of learning math (visual or auditory)
• Students who have missed class time and need to catch up
• Students who need an efficient way to learn about using trigonometric functions
• Students who struggle to understand their teachers
• Students who attend schools without extra math learning resources

## How it works:

• Find videos in our course that cover what you need to learn or review.
• Press play and watch the video lesson.
• Refer to the video transcripts to reinforce your learning.
• Test your understanding of each lesson with short quizzes.
• Verify you're ready by completing the Using Trigonometric Functions chapter exam.

## Why it works:

• Study Efficiently: Skip what you know, review what you don't.
• Retain What You Learn: Engaging animations and real-life examples make topics easy to grasp.
• Be Ready on Test Day: Use the Using Trigonometric Functions chapter exam to be prepared.
• Get Extra Support: Ask our subject-matter experts any trig functions question. They're here to help!
• Study With Flexibility: Watch videos on any web-ready device.

## Students will review:

In this chapter, you'll find answers to questions including:

• What are the definitions of sine, cosine, cotangent, secant and cosecant?
• What are unit circles, special right triangles and special angles?
• How do I use the double angle formula?
• How do I convert between radians and degrees?

13 Lessons in Chapter 20: Using Trigonometric Functions: Help and Review
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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