Calculus 8th Edition

Published by Cengage
ISBN 10: 1285740629
ISBN 13: 978-1-28574-062-1

Chapter 14 - Partial Derivatives - 14.3 Partial Derivatives - 14.3 Exercises - Page 964: 5

Answer

(a) Positive (b) Negative

Work Step by Step

(a) Since, the graph of $f$ increases for $z$, if we start at $(1, 2)$ and move in positive x- direction, this represents the positive values of $f$. Thus,$f_{x} (1,2)$ is positive. (b) Since, the graph of $f$ decrease, if we start at $(1, 2)$ and move in positive y- direction, this represents the negative values of $f$. Thus,$f_{y} (1,2)$is negative.
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.