Sine, Cosine, Tangent and the Unit Circle - Wolfram Demonstrations

A Sine/Cosine Identity - Wolfram Demonstrations Project

Relationship of Sine and Cosine to the Unit Circle - Wolfram Demonstrations Project

Archaic Trigonometry - Wolfram Demonstrations Project

Visualizing Parametrized Curves

Trigonometric Function (Circular Function) - Statistics How To

Illustrating Trigonometric Curves with the Unit Circle - Wolfram Demonstrations Project

Animation: Graphing the Tangent Function Using the Unit Circle

sin cos tan – Geeks out of the box

Angles Measured in Degrees and Radians - Wolfram Demonstrations Project

Representations of Trigonometric and Hyperbolic Functions in Terms of Sector Areas - Wolfram Demonstrations Project