1.340 problem 341

Internal problem ID [7920]

Book: Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section: Chapter 1, linear first order
Problem number: 341.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [_exact]

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

Solution by Maple

Time used: 0.032 (sec). Leaf size: 31

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

\[ y \left (x \right ) = -\left (\operatorname {LambertW}\left (x \,{\mathrm e}^{-x} {\mathrm e}^{-{\mathrm e}^{-x} c_{1}}\right ) {\mathrm e}^{x}+c_{1} \right ) {\mathrm e}^{-x} \]

Solution by Mathematica

Time used: 2.289 (sec). Leaf size: 33

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

\begin{align*} y(x)\to c_1 e^{-x}-W\left (x e^{-x+c_1 e^{-x}}\right ) \\ \end{align*}