Thomas' Calculus 13th Edition

Published by Pearson
ISBN 10: 0-32187-896-5
ISBN 13: 978-0-32187-896-0

Chapter 2: Limits and Continuity - Section 2.6 - Limits Involving Infinity; Asymptotes of Graphs - Exercises 2.6 - Page 99: 85

Answer

$$\frac{5}{2}$$

Work Step by Step

\begin{aligned} \lim _{x \rightarrow \infty}(\sqrt{x^{2}+3 x}-\sqrt{x^{2}-2 x}) &=\lim _{x \rightarrow \infty}[\sqrt{x^{2}+3 x}-\sqrt{x^{2}-2 x}] \cdot\left[\frac{\sqrt{x^{2}+3 x}+\sqrt{x^{2}-2 x}}{\sqrt{x^{2}+3 x}+\sqrt{x^{2}-2 x}}\right]\\ &=\lim _{x \rightarrow \infty} \frac{\left(x^{2}+3 x\right)-\left(x^{2}-2 x\right)}{\sqrt{x^{2}+3 x}+\sqrt{x^{2}-2 x}} \\ &=\lim _{x \rightarrow \infty} \frac{5 x}{\sqrt{x^{2}+3 x}+\sqrt{x^{2}-2 x}}\\ &=\lim _{x \rightarrow \infty} \frac{5}{\sqrt{1+\frac{3}{x}}+\sqrt{1-\frac{2}{x}}}\\ &=\frac{5}{1+1}=\frac{5}{1+1}\\ &=\frac{5}{2} \end{aligned}
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.