| • | Activities in Math: Trigonometry - Three comprehensive modules from Syvum. Each includes theory and explanation, along with practice exercises. |
| • | Addition Formulas for Sines and Cosines - Describes how the Sine and Cosine Addition Formulas can be derived by using vectors and how these formulas can be remembered relatively easily. |
| • | An Index of Trigonometry Help Pages - Provides detailed discussion of trigonometry concepts. Includes examples of varying difficulty. |
| • | An Introduction to Trigonometry - Definitions, basics, functions, and other concepts necessary to understand basic trigonometry. |
| • | Basic Trigonometry - Cosine, sine and tangent are defined. The Pythagorean theorem is illustrated as well the number of degrees in a many sided figure. |
| • | Dave's Short Trig course - Covers basic definitions and concepts in beginning trigonometry. |
| • | Four Branches of Trigonometry - Includes information on the laws of sines and cosines, right triangle trigonometry, and the ambiguous case. |
| • | GCSE Maths: Trigonometry - Explains right triangle properties, historic background, the Pythagorean theorem, and trigonometric functions. Includes definition of terms and illustrations. |
| • | S.O.S. Math - Trigonometry - Covers measuring degrees, equations, and formulas. Includes illustrations and related links. |
| • | Sine and Other Trigonometric Functions - Interactive tests and exercises. |
| • | Trigonometry - Introduction to trigonometry. Includes links to trig-based animations and definitions. |
