#### Katherine Yoshiwara

Available versions | HTML, PDF, and low-cost print |

Source available | PreTeXt source |

Exercises | About 2500 |

Solutions | Short answers to odd numbered problems |

License | GNU Free Documentation License |

- Used for several years at Pierce College (Los Angeles)
- Assumes minimal geometry background
- Each example followed by an in-text exercise
- Each of the first eight chapters contains an engaging activity
- Print version available for $39
- Online homework available at XYZ Homework
- For more information and to download the PDF and to access the online version

This trigonometry textbook can serve students in a variety of programs. Starting with a review of relevant facts from geometry, it covers the material in a standard course, including a treatment of vectors, polar coordinates, and complex numbers.

From the introduction:

Throughout we have been guided by the Rule of Four and use tables and graphical representation to illustrate concepts. We have taken care to include numerical examples and diagrams, both in Examples and in Homework Problems, to offer students some intuitive understanding for the more abstract ideas of trigonometry. Above all, we have tried to focus on the fundamental ideas of trigonometry by introducing them in their most basic form and returning later to look at them in greater detail.

Table of contents:

- Triangles and Circles
- Trigonometric Ratios
- Laws of Sines and Cosines
- Trigonometric Functions
- Equations and Identities
- Radians
- Circular Functions
- Using Identities
- Vectors
- Polar Coordinates and Complex Numbers