Calculus 10th Edition

Published by Brooks Cole
ISBN 10: 1-28505-709-0
ISBN 13: 978-1-28505-709-5

Chapter 6 - Differential Equations - 6.4 Exercises - Page 430: 60

Answer

$${y^2} = 1 + \frac{{C{\text{ }}}}{{{e^{{x^2}}}}}$$

Work Step by Step

$$\eqalign{ & y' + xy = x{y^{ - 1}} \cr & {\text{The differential equation is written in the form}} \cr & y' + P\left( x \right)y = Q\left( x \right){y^n} \cr & y' + xy = x{y^{ - 1}} \to P\left( x \right) = x,{\text{ }}Q\left( x \right) = x,{\text{ }}n = - 1 \cr & {\text{From the book we have that the general solution of a Bernoulli }} \cr & {\text{equation is:}} \cr & {y^{1 - n}}{e^{\int {\left( {1 - n} \right)P\left( x \right)dx} }} = \int {\left( {1 - n} \right)Q\left( x \right){e^{\int {\left( {1 - n} \right)P\left( x \right)dx} }}dx} + C{\text{ }}\left( {\bf{1}} \right) \cr & {\text{Find }}{e^{\int {\left( {1 - n} \right)P\left( x \right)dx} }} \cr & {e^{\int {\left( {1 - n} \right)P\left( x \right)dx} }} = {e^{\int {\left( {1 + 1} \right)\left( x \right)dx} }} = {e^{\int {2x} dx}} = {e^{{x^2}}} \cr & {\text{Substituting }}{e^{\int {\left( {1 - n} \right)P\left( x \right)dx} }},{\text{ }}n,{\text{ and }}Q\left( x \right){\text{ into }}\left( {\bf{1}} \right) \cr & {y^{1 + 1}}{e^{{x^2}}} = \int {\left( {1 + 1} \right)\left( x \right){e^{{x^2}}}dx} + C{\text{ }} \cr & {y^2}{e^{{x^2}}} = \int {2x{e^{{x^2}}}dx} + C{\text{ }} \cr & {\text{Integrating}} \cr & {y^2}{e^{{x^2}}} = {e^{{x^2}}} + C{\text{ }} \cr & {y^2} = \frac{{{e^{{x^2}}}}}{{{e^{{x^2}}}}} + \frac{{C{\text{ }}}}{{{e^{{x^2}}}}} \cr & {\text{Simplifying}} \cr & {y^2} = 1 + \frac{{C{\text{ }}}}{{{e^{{x^2}}}}} \cr} $$
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.