Calculus (3rd Edition)

Published by W. H. Freeman
ISBN 10: 1464125260
ISBN 13: 978-1-46412-526-3

Chapter 17 - Line and Surface Integrals - 17.1 Vector Fields - Exercises - Page 919: 44

Answer

$f\left( {x,y,z} \right) = z{{\rm{e}}^{{x^2}}}$ is a potential function for ${\bf{F}} = \left( {2xz{{\rm{e}}^{{x^2}}},0,{{\rm{e}}^{{x^2}}}} \right)$.

Work Step by Step

Suppose that $f$ is a potential function for ${\bf{F}}$. Then, $\nabla f = {\bf{F}} = \left( {2xz{{\rm{e}}^{{x^2}}},0,{{\rm{e}}^{{x^2}}}} \right)$. Since $\nabla f = \left( {\frac{{\partial f}}{{\partial x}},\frac{{\partial f}}{{\partial y}},\frac{{\partial f}}{{\partial z}}} \right)$, so (1) ${\ \ \ \ \ }$ $\left( {\frac{{\partial f}}{{\partial x}},\frac{{\partial f}}{{\partial y}},\frac{{\partial f}}{{\partial z}}} \right) = \left( {2xz{{\rm{e}}^{{x^2}}},0,{{\rm{e}}^{{x^2}}}} \right)$ There exists a function $f\left( {x,y,z} \right) = z{{\rm{e}}^{{x^2}}}$ such that equation (1) is satisfied: $\frac{{\partial f}}{{\partial x}} = 2xz{{\rm{e}}^{{x^2}}}$, ${\ \ \ \ }$ $\frac{{\partial f}}{{\partial y}} = 0$, ${\ \ \ \ }$ $\frac{{\partial f}}{{\partial z}} = {{\rm{e}}^{{x^2}}}$ So, $f\left( {x,y,z} \right) = z{{\rm{e}}^{{x^2}}}$ is a potential function for ${\bf{F}} = \left( {2xz{{\rm{e}}^{{x^2}}},0,{{\rm{e}}^{{x^2}}}} \right)$.
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.