Precalculus (6th Edition) Blitzer

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

Chapter 2 - Section 2.7 - Polynomial and Rational Inequalities - Exercise Set - Page 413: 57

Answer

$(-\infty,\frac{1}{2})\cup[\frac{7}{5},\infty)$

Work Step by Step

Step 1. Rewrite the inequality as $\frac{x+4}{2x-1}-3\leq0$ which gives $\frac{x+4-6x+3}{2x-1}\leq0$, $\frac{-5x+7}{2x-1}\leq0$ and $\frac{5x-7}{2x-1}\geq0$ Thus the boundary points are $x=1/2,7/5$ Step 2. Using the test points to examine signs across the boundary points, we have $...(+)...(1/2)...(-)...(7/5)...(+)...$ Thus the solutions are $x\lt\frac{1}{2}$ plus $x\geq\frac{7}{5}$ Step 3. We can express the solutions on a real number line as shown in the figure. Step 4. We can express the solutions in interval notation as $(-\infty,\frac{1}{2})\cup[\frac{7}{5},\infty)$
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.