Trigonometry 7th Edition

Published by Cengage Learning
ISBN 10: 1111826854
ISBN 13: 978-1-11182-685-7

Chapter 2 - Section 2.3 - Solving Right Triangles - 2.3 Problem Set - Page 83: 74

Answer

$\sin\theta=-\frac{2\sqrt 5}{5}$ $\sec\theta=\sqrt 5$ $\csc\theta=-\frac{\sqrt 5}{2}$ $\tan\theta=-2$ $\cot\theta=-\frac{1}{2}$

Work Step by Step

$\sin^{2}\theta+\cos^{2}\theta=1\implies\sin^{2}\theta=1-\cos^{2}\theta$ $=1-(\frac{1}{\sqrt 5})^{2}=\frac{4}{5}$ $\sin\theta$ is negative in the fourth quadrant. Therefore, $\sin\theta=-\sqrt {\frac{4}{5}}=-\frac{2}{\sqrt 5}=-\frac{2\sqrt 5}{5}$ $\sec\theta=\frac{1}{\cos\theta}=\sqrt 5$ $\csc\theta=\frac{1}{\sin\theta}=-\frac{\sqrt 5}{2}$ $\tan\theta=\frac{\sin\theta}{\cos\theta}=\frac{-\frac{2}{\sqrt 5}}{\frac{1}{\sqrt 5}}=-2$ $\cot\theta=\frac{1}{\tan\theta}=-\frac{1}{2}$
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.