- Khan Academy: This website breaks down each subject area by using videos, examples and explanations.
- Dave’s Short Trig Course: Easy to navigate, this site has a table of contents containing sixteen different topics, including applications of trigonometry, angle measurement, chords, sines, cosines, tangents and slope, right triangles, trigonometric functions, and the area of a triangle. All sections contain in-depth explanations as well as graphs and diagrams.
- S.O.S. Mathematics: Trigonometry: This site is equipped with detailed explanations and examples of angle measures, trigonometric functions, and trigonometric equations. In addition, there is an entire section devoted to solving equations, with sample problems and solutions. A table of trigonometric identities is also available as a helpful reference.
- Trigonometry Help is a comprehensive resource for students of trigonometry, complete with detailed descriptions of basic terms (including types of angles, laws, and formulas), lists of trigonometry identities, tips for picking a tutor, and even a brief history of the subject.