8.13 problem 218

Internal problem ID [3474]

Book: Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section: Various 8
Problem number: 218.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [[_homogeneous, `class A`], _dAlembert]

\[ \boxed {x y^{\prime }-y+2 x \tanh \left (\frac {y}{x}\right )=0} \]

Solution by Maple

Time used: 0.985 (sec). Leaf size: 34

dsolve(x*diff(y(x),x) = y(x)-2*x*tanh(y(x)/x),y(x), singsol=all)
 

\begin{align*} y \left (x \right ) &= \operatorname {arctanh}\left (\frac {1}{\sqrt {-c_{1} x^{4}+1}}\right ) x \\ y \left (x \right ) &= -\operatorname {arctanh}\left (\frac {1}{\sqrt {-c_{1} x^{4}+1}}\right ) x \\ \end{align*}

Solution by Mathematica

Time used: 11.37 (sec). Leaf size: 21

DSolve[x y'[x]==y[x]-2 x Tanh[y[x]/x],y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to x \text {arcsinh}\left (\frac {e^{c_1}}{x^2}\right ) \\ y(x)\to 0 \\ \end{align*}