Trigonometry (10th Edition)

Published by Pearson
ISBN 10: 0321671775
ISBN 13: 978-0-32167-177-6

Chapter 5 - Trigonometric Identities - Section 5.5 Double-Angle Identities - 5.5 Exercises - Page 231: 66

Answer

$$\sin102^\circ-\sin95^\circ=2\cos(\frac{197^\circ}{2})\sin(\frac{7^\circ}{2})$$

Work Step by Step

$$A=\sin102^\circ-\sin95^\circ$$ The sum-to-product identity that will be applied here is $$\sin X-\sin Y=2\cos(\frac{X+Y}{2})\sin(\frac{X-Y}{2})$$ Therefore, A would be $$A=2\cos[\frac{102^\circ+95^\circ}{2}]\sin[\frac{102^\circ-95^\circ}{2}]$$ $$A=2\cos(\frac{197^\circ}{2})\sin(\frac{7^\circ}{2})$$
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.