# Ch 20: Trigonometric Functions: Homework Help

### About This Chapter

## How it works:

- Identify which concepts are covered on your trigonometric functions homework.
- Find videos on those topics within this chapter.
- Watch fun videos, pausing and reviewing as needed.
- Complete sample problems and get instant feedback.
- Finish your trigonometric functions homework with ease!

## Topics from your homework you'll be able to complete:

- Defining the common properties of special right triangles
- Memorizing the first quadrant and highlighting the first quadrant of the unit circle
- Solving practice problems using circular function definitions
- Learning the double angle formula
- Relating right triangles to sine and cosine

### 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. 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.

### 3. 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.

### 4. 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.

### 5. 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.

### 6. 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.

### 7. 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.

### 8. 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.

### 9. 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.

### 10. Converting Between Radians and Degrees

Angles can be measured in degrees or radians. This lesson will explore the difference and provide you with a simple calculation that can be used to convert degrees into radians and radians into degrees.

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### Other Chapters

Other chapters within the High School Trigonometry: Homework Help Resource course

- Real Numbers - Types and Properties: Homework Help
- Working with Linear Equations in Trigonometry: Homework Help
- Working with Inequalities in Trigonometry: Homework Help
- Absolute Value Equations in Trigonometry: Homework Help
- Working with Complex Numbers in Trigonometry: Homework Help
- Systems of Linear Equations in Trigonometry: Homework Help
- Mathematical Modeling in Trigonometry: Homework Help
- Introduction to Quadratics in Trigonometry: Homework Help
- Working with Quadratic Functions in Trigonometry: Homework Help
- Coordinate Geometry Review: Homework Help
- Functions for Trigonometry: Homework Help
- Understanding Function Operations in Trigonometry: Homework Help
- Graph Symmetry in Trigonometry: Homework Help
- Graphing with Functions in Trigonometry: Homework Help
- Basic Polynomial Functions in Trigonometry: Homework Help
- Higher-Degree Polynomial Functions in Trigonometry: Homework Help
- Rational Functions in Trigonometry: Homework Help
- Homework Help for Trig Function Graphs & Rational Expressions in Trigonometry
- Exponential & Logarithmic Functions in Trigonometry: Homework Help
- Geometry in Trigonometry: Homework Help
- Triangle Trigonometry: Homework Help
- Working with Trigonometric Graphs: Homework Help
- Trigonometric Equations: Homework Help
- Working with Trigonometric Identities: Homework Help
- Applications of Trigonometry: Homework Help
- Analytic Geometry & Conic Sections in Trigonometry: Homework Help
- Vectors, Matrices & Determinants in Trigonometry: Homework Help
- Polar Coordinates & Parameterizations: Homework Help
- Circular Arcs, Circles & Angles: Homework Help