Trigonometry (10th Edition)

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

Chapter 2 - Acute Angles and Right Triangles - Section 2.3 Finding Trigonometric Function Values Using a Calculator - 2.3 Exercises: 36

Answer

It could be found by finding the terminal angle of $\cos$ 2000$^{\circ}$, and then using that terminal angle to find the reference angle which would be significantly smaller, and could be used to evaluate the equation.

Work Step by Step

2000$^{\circ}$ - 5(360$^{\circ}$) = 200$^{\circ}$ 200$^{\circ}$ = The terminal angle of 2000$^{\circ}$ 180$^{\circ}$ - 200$^{\circ}$ = -20$^{\circ}$ -20$^{\circ}$ = The reference angle of 200$^{\circ}$ Therefore: $\cos$ 2000$^{\circ}$ = -$\cos$ 20$^{\circ}$ -$\cos$ 20$^{\circ}$ = -0.93969262
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.