Calculus: Early Transcendentals 8th Edition

Published by Cengage Learning
ISBN 10: 1285741552
ISBN 13: 978-1-28574-155-0

Chapter 7 - Section 7.8 - Improper Integrals - 7.8 Exercises - Page 534: 21

Answer

Divergent

Work Step by Step

$$\int_{1}^{\infty }\frac{lnx}{x}dx=\lim_{t\rightarrow \infty}\int_{1}^{t}\frac{lnx}{x}dx$$ $$=\lim_{t\rightarrow \infty}\int_{1}^{t}lnx\ d(lnx)$$ $$=\lim_{t\rightarrow \infty} \left|\frac{(lnx)^{2}}{2}\right |_{1}^{t}$$ $$= \lim_{t\rightarrow \infty} \frac{(ln\,t)^{2}}{2}$$ $$=\infty,\ divergent$$
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.