# Ch 20: Using Trigonometric Functions: Tutoring Solution

### About This Chapter

## How it works:

- Begin your assignment or other precalculus work.
- Identify the trigonometric functions concepts that you're stuck on.
- Find fun videos on the topics you need to understand.
- Press play, watch and learn!
- Complete the quizzes to test your understanding.
- As needed, submit a question to one of our instructors for personalized support.

## Who's it for?

This chapter of our high school precalculus tutoring solution will benefit any student who is trying to learn how to use trig functions and earn better grades. This resource can help students including those who:

- Struggle with understanding sine, cosine, cotangent, secant, cosecant, the double angle formula or any other trigonometric functions topic
- Have limited time for studying
- Want a cost effective way to supplement their math learning
- Prefer learning math visually
- Find themselves failing or close to failing their trigonometric functions unit
- Cope with ADD or ADHD
- Want to get ahead in precalculus
- Don't have access to their math teacher outside of class

## Why it works:

**Engaging Tutors:**We make learning how to use trig functions simple and fun.**Cost Efficient:**For less than 20% of the cost of a private tutor, you'll have unlimited access 24/7.**Consistent High Quality:**Unlike a live precalculus tutor, these video lessons are thoroughly reviewed.**Convenient:**Imagine a tutor as portable as your laptop, tablet or smartphone. Learn how to use trig functions on the go!**Learn at Your Pace:**You can pause and rewatch lessons as often as you'd like, until you master the material.

## Learning Objectives

- Become familiar with the basic trigonometric functions of sine, cosine and tangent.
- Understand the trigonometric functions of cotangent, secant and cosecant.
- Memorize the first quadrant of the unit circle.
- Use the unit circle to relate right triangles to sine and cosine.
- Solve problems involving circular trigonometric functions.
- Describe the types and properties of special right triangles.
- Determine the trigonometric function values of special angles.
- Become familiar with the law of sines and law of cosines.
- Discuss the double angle formula.
- Convert between radians and degrees.

### 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. 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.

### 4. 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.

### 5. 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.

### 6. 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.

### 7. 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.

### 8. 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.

### 9. 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.

### 10. 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.

### 11. 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.

### 12. Inversely Proportional: Definition, Formula & Examples

In this lesson, you will understand the definition of the term 'inversely proportional' and be able to write the algebraic expressions for inverse variations. You will also be able to apply the inverse variation relationships to solve different types of problems.

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### Other Chapters

Other chapters within the High School Precalculus: Tutoring Solution course

- Working with Linear Equations: Tutoring Solution
- Working With Inequalities: Tutoring Solution
- Absolute Value Equations: Tutoring Solution
- Working with Complex Numbers: Tutoring Solution
- Systems of Linear Equations: Tutoring Solution
- Mathematical Modeling: Tutoring Solution
- Introduction to Quadratics in Precalculus: Tutoring Solution
- Working with Quadratic Functions: Tutoring Solution
- Geometry Basics for Precalculus: Tutoring Solution
- Functions - Basics for Precalculus: Tutoring Solution
- Understanding Function Operations: Tutoring Solution
- Graph Symmetry: Tutoring Solution
- Graphing with Functions: Tutoring Solution
- Rate of Change in Precalculus: Tutoring Solution
- Polynomial Functions Basics: Tutoring Solution
- Higher-Degree Polynomial Functions: Tutoring Solution
- Rational Functions and Difference Quotients: Tutoring Solution
- Rational Expressions and Function Graphs: Tutoring Solution
- Exponential Functions & Logarithmic Functions: Tutoring Solution
- Trigonometric Graphs: Tutoring Solution
- Solving Trigonometric Equations: Tutoring Solution
- Trigonometric Identities: Tutoring Solution
- Trigonometric Applications in Precalculus: Tutoring Solution
- Graphing Piecewise Functions: Tutoring Solution
- Vectors, Matrices and Determinants: Tutoring Solution
- Mathematical Sequences and Series: Tutoring Solution
- Sets in Algebra: Tutoring Solution
- Analytic Geometry and Conic Sections: Tutoring Solution
- Polar Coordinates and Parameterizations: Tutoring Solution
- Continuity in Precalculus: Tutoring Solution
- Limits in Precalculus: Tutoring Solution