4.15 problem 15

Internal problem ID [6196]

Book: Differential Equations: Theory, Technique, and Practice by George Simmons, Steven Krantz. McGraw-Hill NY. 2007. 1st Edition.
Section: Chapter 1. What is a differential equation. Section 1.5. Exact Equations. Page 20
Problem number: 15.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [_separable]

\[ \boxed {x \ln \left (y\right )+y x +\left (\ln \left (x \right ) y+y x \right ) y^{\prime }=0} \]

Solution by Maple

Time used: 0.0 (sec). Leaf size: 28

dsolve((x*ln(y(x))+x*y(x))+(y(x)*ln(x)+x*y(x))*diff(y(x),x)=0,y(x), singsol=all)
 

\[ \int \frac {x}{\ln \left (x \right )+x}d x +\int _{}^{y \left (x \right )}\frac {\textit {\_a}}{\textit {\_a} +\ln \left (\textit {\_a} \right )}d \textit {\_a} +c_{1} = 0 \]

Solution by Mathematica

Time used: 36.692 (sec). Leaf size: 54

DSolve[(x*Log[y[x]]+x*y[x])+(y[x]*Log[x]+x*y[x])*y'[x]==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to \text {InverseFunction}\left [\int _1^{\text {$\#$1}}\frac {K[1]}{K[1]+\log (K[1])}dK[1]\&\right ]\left [\int _1^x-\frac {K[2]}{K[2]+\log (K[2])}dK[2]+c_1\right ] y(x)\to W(1) \end{align*}