Introduction
Our discussion so far has been limited to right-angled triangles where, apart from the right-angle itself, all angles are necessarily less than . We now extend the definitions of the trigonometric functions to any size of angle, which greatly broadens the range of applications of trigonometry.
Prerequisites
- have a basic knowledge of the geometry of triangles
Learning Outcomes
- express angles in radians
- define trigonometric functions generally
- sketch the graphs of the three main trigonometric functions: