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Calculus III

Course: Trigonometry
Topic: Circular Functions
Subtopic: Reference Angle

Overview

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.

Objectives

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

• 3.1.1 Use the reference angle theorem to evaluate trig functions
• 3.1.2 Evalute trig functions of "nice" angles by hand
• 3.1.3 Evaluate trig functions of any angle electronically
• 3.1.4 Find inverse trig functions (algebraically and electronically)
• 3.1.5 Know which trig functions are even and which are odd
• 3.1.6 Know the formulae for even/odd trig functions and be able to use them to evaluate trig functions of negative angles

Terminology

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

Mini-Lectures and Examples

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