4  Trigonometric Functions

4.1 Measuring Rotation: Angles and Radian Measure

This section is under development.

4.2 Around and Around: Trigonometric Functions and the Unit Circle

This section is under development.

4.3 Triangles in Action: Right Triangle Trigonometry

This section is under development.

4.4 Any Angle, Any Quadrant: Trigonometric Functions of Any Angle

This section is under development.