University Calculus: Early Transcendentals (3rd Edition)

Published by Pearson
ISBN 10: 0321999584
ISBN 13: 978-0-32199-958-0

Chapter 14 - Section 14.1 - Double and Iterated Integrals over Rectangles - Exercises - Page 759: 13

Answer

$\ln 2$

Work Step by Step

Re-arrange the given integral as follows: $\int_{1}^{4} [\dfrac{\ln x}{xy} dx]_{1}^{e}=\dfrac{1}{4} \int_{1}^{4}\dfrac{\ln x}{x} dx$ Plug $ \ln x=p \implies dp=\dfrac{dx}{x}$ This implies that $(\dfrac{1}{4}) \int_{1}^{4} \dfrac{p^2}{2}|_1^e =(\dfrac{1}{4}) \dfrac{\ln ^2 x}{2}]_1^e$ Hence, $\int_1^{4} \dfrac{dy}{2y} =\dfrac{1}{2} \ln (y)|_1^4$ or, $\dfrac{\ln 4}{2}=\ln 2$
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.