Calculus: Early Transcendentals 9th Edition

Published by Cengage Learning
ISBN 10: 1337613924
ISBN 13: 978-1-33761-392-7

Chapter 2 - Section 2.6 - Limits at Infinity; Horizontal Asymptotes - 2.6 Exercises - Page 138: 11

Answer

We could guess that the value of the limit $\lim\limits_{x \to \infty}\frac{x^2}{2^x}$ is $0$ On the graph, we can see that the function approaches $0$ as $x$ becomes more positive. We can see that $\lim\limits_{x \to \infty}\frac{x^2}{2^x} = 0$

Work Step by Step

$f(x) = \frac{x^2}{2^x}$ We can evaluate $f(x)$ at various values of $x$: $f(0) = \frac{0^2}{2^0} = 0$ $f(1) = \frac{1^2}{2^1} = 0.5$ $f(2) = \frac{2^2}{2^2} = 1$ $f(3) = \frac{3^2}{2^3} = 1.125$ $f(4) = \frac{4^2}{2^4} = 1$ $f(5) = \frac{5^2}{2^5} = 0.78125$ $f(6) = \frac{6^2}{2^6} = 0.5625$ $f(7) = \frac{7^2}{2^7} = 0.3828125$ $f(8) = \frac{8^2}{2^8} = 0.25$ $f(9) = \frac{9^2}{2^9} = 0.158203125$ $f(10) = \frac{10^2}{2^{10}} = 0.09765625$ $f(20) = \frac{20^2}{2^{20}} = 0.00038147$ $f(50) = \frac{50^2}{2^{50}} = 0.00000000000222$ $f(100) = \frac{100^2}{2^{100}} = 7.888609\times 10^{-27}$ We could guess that the value of the limit $\lim\limits_{x \to \infty}\frac{x^2}{2^x}$ is $0$ On the graph, we can see that the function approaches $0$ as $x$ becomes more positive. We can see that $\lim\limits_{x \to \infty}\frac{x^2}{2^x} = 0$
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.