# Ch 11: Introduction to Trigonometric Functions

### About This Chapter

## Introduction to Trigonometric Functions - Chapter Summary

This fun chapter teaches you about solving trigonometric functions that involve cosines, sines and inverse trigonometry functions. You'll learn an easy pattern to memorize the points, radians and degree measures in the first quadrant of the unit circle. Other topics include using the unit circle to help better understand trigonometric concepts and the two special right triangles that can help you solve triangle problems. After you work through this chapter, you will be able to:

- Identify what secant, cosecant and cotangent functions are
- Give examples of radians and degrees
- Use the unit circle to find angles in radians
- Describe the six trigonometric functions
- Use the double angle formula

Engaging video and text lessons outline key trig functions in an easy-to-follow format. Before or after reviewing the lessons, take the self-assessment quizzes to gauge your understanding of these topics. To go back and re-watch just a portion of a video lesson, use the video tabs feature in the Timeline. Feel free to study any time you'd like, 24 hours a day, on any computer, tablet or mobile phone.

### 1. Trigonometry: Sine and Cosine

Learn an easy trick to help you solve trigonometry problems, including problems with sine, cosine and inverse trig functions. At the end of this lesson, you'll know what SohCahToa means and how to use it.

### 2. Other Trigonometric Functions: Cotangent, Secant & Cosecant

After watching this video lesson, you will understand how the trigonometric functions cotangent, secant, and cosecant are related to the sine, cosine, and tangent functions.

### 3. Radians and Degrees: Definition & Examples

Radians and degrees are two ways of measuring angles. In this lesson, you will learn the definition of each method, see how to convert from one to the other and work some practice problems. There is also a quiz at the end of the lesson.

### 4. Unit Circle: Memorizing the First Quadrant

Memorizing the unit circle can be a daunting task, but this lesson will show you a pattern to help you memorize the points, degree measures, and radian measures for the entire first quadrant.

### 5. Using Unit Circles to Relate Right Triangles to Sine & Cosine

The unit circle is a helpful tool for understanding trigonometric concepts. In this lesson, we'll look at right triangles on the unit circle to better grasp sine and cosine.

### 6. Practice Problems with Circular Trigonometric Functions

After watching this video lesson, you will be able to use the unit circle to help you find your answer to trig problems without making too many calculations. Watch and learn how you can find your angle in radians on the unit circle.

### 7. Special Right Triangles: Types and Properties

Not all right triangles are the same. In this lesson, we'll look at two special right triangles (30-60-90 and 45-45-90) that have unique properties to help you quickly and easily solve certain triangle problems.

### 8. Trigonometric Function Values of Special Angles

After watching this video lesson, you will better understand the six trigonometric functions. You will also know what special angles there are and what the trigonometric values for these special angles are.

### 9. Law of Sines: Definition and Application

Don't get stuck trying to find missing sides or angles in a triangle. Use the Law of Sines to rescue you from any perilous triangle in which you have just a few pieces of information.

### 10. Law of Cosines: Definition and Application

In this lesson, we'll learn how to solve problems involving three sides and one angle in a triangle. The Law of Cosines, a modification of the Pythagorean Theorem, will save the day.

### 11. The Double Angle Formula

When you encounter a doubled angle, there are special formulas that can help you handle trigonometric value. In this lesson, we'll define and practice using the double angle formulas for sine, cosine and tangent.

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### Other Chapters

Other chapters within the BITSAT Exam - Math: Study Guide & Test Prep course

- Expressions & Reasoning in Math
- Complex Numbers & Polynomials in Algebra
- Introduction to Quadratics
- Working with Quadratic Functions Overview
- Mathematical Sequences & Series Overview
- Series & Sequences Application
- Exponential Functions & Logarithmic Equations
- Binomial Theorem Overview
- Overview of Matrices & Determinants
- Sets & Relations in Math
- Trigonometric Identities Overview
- Real World Trigonometric Applications
- Operating with Functions
- Solving Inequalities
- Two-Dimensional Coordinate Geometry
- Straight Lines & Angles in Coordinate Geometry
- Circular Arc & Circles in Coordinate Geometry
- Conic Sections in Coordinate Geometry
- Three-Dimensional Coordinate Geometry
- Limits & Continuity in Differential Calculus
- Calculating Derivatives
- Differentiable Functions & Min-Max Problems
- Differentiability in Integral Calculus
- Overview of Probability in Calculus
- Vectors & Scalars in Math
- Dispersion & Frequency Distributions in Statistics
- Linear Programming & Systems of Equations
- Definite Integrals
- Permutation & Combination
- Mathematical Modeling Overview
- BITSAT Exam - Math Flashcards