# Ch 43: WEST Math: Trigonometric Functions

### About This Chapter

## WEST Math: Trigonometric Functions - Chapter Summary

As you navigate through the short, entertaining video lessons in this chapter, you will review the trigonometric functions you need to know for the WEST Math assessment. Chapter topics include:

- Sines and cosines
- The Pythagorean theorem
- Cotangents, secants and cosecants
- Trigonometric ratios
- How to solve a right triangle
- Methods for finding area
- Special angles and the double angle formula

A short quiz after each lesson allows you to practice using the ideas you've covered and determine which areas need additional review. If you need help with the trigonometric concepts in this chapter, please reach out to our instructors. They will be happy to offer guidance.

### 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. Trigonometry and the Pythagorean Theorem

Explore how the Pythagorean Theorem can be used in conjunction with trigonometric functions. In this lesson, take an inverse trigonometric function, and define all three sides of a right triangle.

### 3. 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.

### 4. Trigonometric Ratios and Similarity

Where do terms like sine, cosine and tangent come from? In this lesson, we'll learn about how similarity with right triangles leads to trigonometric ratios.

### 5. 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.

### 6. 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.

### 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 NES Mathematics - WEST (304): Practice & Study Guide course

- WEST Math: Properties of Real Numbers
- WEST Math: Fractions
- WEST Math: Decimals & Percents
- WEST Math: Ratios & Proportions
- WEST Math: Units of Measure & Conversions
- WEST Math: Logic
- WEST Math: Reasoning
- WEST Math: Vector Operations
- WEST Math: Matrix Operations & Determinants
- WEST Math: Exponents & Exponential Expressions
- WEST Math: Algebraic Expressions
- WEST Math: Linear Equations
- WEST Math: Inequalities
- WEST Math: Absolute Value
- WEST Math: Quadratic Equations
- WEST Math: Polynomials
- WEST Math: Rational Expressions
- WEST Math: Radical Expressions
- WEST Math: Systems of Equations
- WEST Math: Complex Numbers
- WEST Math: Functions
- WEST Math: Piecewise Functions
- WEST Math: Exponential & Logarithmic Functions
- WEST Math: Continuity of a Function
- WEST Math: Limits
- WEST Math: Rate of Change
- WEST Math: Derivative Rules
- WEST Math: Graphing Derivatives
- WEST Math: Applications of Derivatives
- WEST Math: Area Under the Curve & Integrals
- WEST Math: Integration Techniques
- WEST Math: Applications of Integration
- WEST Math: Foundations of Geometry
- WEST Math: Geometric Figures
- WEST Math: Properties of Triangles
- WEST Math: Triangle Theorems & Proofs
- WEST Math: Parallel Lines & Polygons
- WEST Math: Quadrilaterals
- WEST Math: Circles & Arc of a Circle
- WEST Math: Conic Sections
- WEST Math: Geometric Solids
- WEST Math: Analytical Geometry
- WEST Math: Trigonometric Graphs
- WEST Math: Solving Trigonometric Equations
- WEST Math: Trigonometric Identities
- WEST Math: Sequences & Series
- WEST Math: Set Theory
- WEST Math: Statistics Overview
- WEST Math: Summarizing Data
- WEST Math: Tables, Plots & Graphs
- WEST Math: Probability
- WEST Math: Discrete Probability Distributions
- WEST Math: Continuous Probability Distributions
- WEST Math: Sampling
- NES Mathematics WEST Flashcards