Precalculus (6th Edition) Blitzer

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

Chapter 5 - Review Exercises - Page 707: 8

Answer

The expression on the left side is equal to the expression on the right side.

Work Step by Step

We have the expression on the left side $\frac{\cos x}{1-\sin x}$, which can be simplified by multiplying and dividing the expression by $1+\sin x$. As per the Pythagorean identity, ${{\sin }^{2}}x+{{\cos }^{2}}x=1$. Therefore, ${{\cos }^{2}}x=1-{{\sin }^{2}}x$. $\begin{align} & \frac{\cos x}{1-\sin x}=\frac{\cos x}{1-\sin x}.\frac{1+\sin x}{1+\sin x} \\ & =\frac{\cos x\left( 1+\sin x \right)}{1-{{\sin }^{2}}x} \\ & =\frac{\cos x\left( 1+\sin x \right)}{{{\cos }^{2}}x} \\ & =\frac{\left( 1+\sin x \right)}{\cos x} \end{align}$ Hence, the expression on the left side is equal to the expression on the right side.
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.