Course: Trigonometry
Topic: Circular Functions
Subtopic: Reference Angle


To some degree (mind the pun) we have been using reference angles subtly already, but now we will make them official. This will enable us to evaluate trig functions of any angle and to more accurately take inverse trig functions.


By the end of this topic you should know and be prepared to be tested on:


Terms you should be able to define: reference angle, inverse trigonometric function, odd function (algebraically), even function (algebraically)

Mini-Lectures and Examples

STUDY: SOH-CAH-TOA Definition of Trig Functions & Calculators & Reference Angles

Supplemental Resources (optional)

Videos from James Sousa's MathIsPower4U:
Mini-Lesson: Determine Trigonometric Function Values using Reference Angles and Reference Triangles
Example: Determine Trig Function Values Using Reference Triangles

rev. 2020-10-10