University Calculus: Early Transcendentals (3rd Edition)

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

Chapter 13 - Section 13.2 - Limits and Continuity in Higher Dimensions - Exercises - Page 693: 70

Answer

$|f(x,y) -f(0,0) | \lt \epsilon $

Work Step by Step

We have $f(x,y)=\dfrac{y}{x^2+1} ; \\f(0,0)=0$ Now, $|f(x,y) -f(0,0) | \lt \epsilon $ $ \implies |\dfrac{y}{x^2+1}-0| \lt 0.05 $ $\implies \dfrac{|y|}{x^2+1} \lt 0.05$ Since,$\dfrac{|y|}{x^2+1} \leq \sqrt {x^2+y^2 }$ Now, $\sqrt {x^2+y^2 } \lt 0.05$ Consider $\delta =0.05$ and $\sqrt {x^2+y^2 } \lt \delta$ Thus, we have $|f(x,y) -f(0,0) | \lt \epsilon $
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.