2.264 problem 840

Internal problem ID [9175]

Book: Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section: Chapter 1, Additional non-linear first order
Problem number: 840.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [[_1st_order, _with_linear_symmetries]]

\[ \boxed {y^{\prime }-\frac {\left ({\mathrm e}^{-\frac {y}{x}} y+{\mathrm e}^{-\frac {y}{x}} x +x^{3}\right ) {\mathrm e}^{\frac {y}{x}}}{x}=0} \]

Solution by Maple

Time used: 0.016 (sec). Leaf size: 21

dsolve(diff(y(x),x) = (exp(-y(x)/x)*y(x)+exp(-y(x)/x)*x+x^3)*exp(y(x)/x)/x,y(x), singsol=all)
 

\[ y \left (x \right ) = \left (\ln \left (3\right )+\ln \left (\frac {x}{-x^{3}+c_{1}}\right )\right ) x \]

Solution by Mathematica

Time used: 4.19 (sec). Leaf size: 43

DSolve[y'[x] == (E^(y[x]/x)*(x/E^(y[x]/x) + x^3 + y[x]/E^(y[x]/x)))/x,y[x],x,IncludeSingularSolutions -> True]
                                                                                    
                                                                                    
 

\begin{align*} y(x)\to -x \log \left (\frac {-x^3+e^{3 c_1}}{3 x}\right ) \\ y(x)\to -x \log \left (-\frac {x^2}{3}\right ) \\ \end{align*}