71.8.34 problem 12 (a)

Internal problem ID [14468]
Book : Ordinary Differential Equations by Charles E. Roberts, Jr. CRC Press. 2010
Section : Chapter 2. The Initial Value Problem. Exercises 2.4.4, page 115
Problem number : 12 (a)
Date solved : Tuesday, January 28, 2025 at 06:39:40 AM
CAS classification : [[_homogeneous, `class A`], _rational, _dAlembert]

\begin{align*} y^{\prime }&=\frac {x y}{x^{2}+y^{2}} \end{align*}

With initial conditions

\begin{align*} y \left (0\right )&=1 \end{align*}

Solution by Maple

Time used: 4.071 (sec). Leaf size: 16

dsolve([diff(y(x),x)=x*y(x)/(x^2+y(x)^2),y(0) = 1],y(x), singsol=all)
 
\[ y = \sqrt {\frac {x^{2}}{\operatorname {LambertW}\left (x^{2}\right )}} \]

Solution by Mathematica

Time used: 7.124 (sec). Leaf size: 15

DSolve[{D[y[x],x]==x*y[x]/(x^2+y[x]^2),{y[0]==1}},y[x],x,IncludeSingularSolutions -> True]
 
\[ y(x)\to \frac {x}{\sqrt {W\left (x^2\right )}} \]