Precalculus (6th Edition) Blitzer

Published by Pearson
ISBN 10: 0-13446-914-3
ISBN 13: 978-0-13446-914-0

Chapter 4 - Section 4.4 - Trigonometric Functions of Any Angle - Exercise Set: 41



Work Step by Step

RECALL: The following are the means on how to find the reference angle of an angle $\theta$ based on its position: (1) Quadrant I: $\theta$ (itself) (2) Quadrant II: $\pi-\theta$ (3) Quadrant III: $\theta - \pi$ (4) Quadrant IV: $2\pi-\theta$ $\frac{7\pi}{4}$ is in Quadrant IV. Thus, using formula (4) above gives: reference angle of $\frac{7\pi}{4}$ = $2\pi-\dfrac{7\pi}{4}=\dfrac{8\pi}{4}-\dfrac{7\pi}{4} = \dfrac{\pi}{4}$
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.