University Calculus: Early Transcendentals (3rd Edition)

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

Chapter 9 - Section 9.1 - Sequences - Exercises - Page 489: 113

Answer

The sequence $a_n$ is not monotonic and bounded.

Work Step by Step

Our aim is to find out if the sequence $a_n$ is monotonic. In order to this, we will consider $a_n=\dfrac{2^n 3^n}{n!}=\dfrac{6^n}{n!}$ for all $n \in N$ Also, $\lim\limits_{n \to \infty} a_n=\lim\limits_{n \to \infty}\dfrac{6^n}{n!}=0$ Thus, $a_n$ is bounded because the sequence converges to $0$ Now, $a_1= \dfrac{6^1}{1!}=6 \lt a_2=\dfrac{6^2}{2!}$ but $a_6= \dfrac{6^6}{6!}\gt a_7=\dfrac{6^7}{7!}$ Hence, the sequence $a_n$ is not monotonic and bounded.
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.