## Trigonometry

Pre ? Calculus Math 40S: Explained! www.math40s.com 9 Pre ? Calculus Math 40S: Explained! www.math40s.com 10 Trigonometry Lesson 2 Part One ? The Unit Circle The Unit Circle What you see here is the unit circle. This is a useful tool in: a) Comparing angles in degrees & radians. b) Finding exact values of the six trigonometric ratios. It is very important you memorize the unit circle