23.1.735 problem 733

Internal problem ID [5342]
Book : Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section : Part II. Chapter 1. THE DIFFERENTIAL EQUATION IS OF FIRST ORDER AND OF FIRST DEGREE, page 223
Problem number : 733
Date solved : Tuesday, September 30, 2025 at 12:31:09 PM
CAS classification : [[_homogeneous, `class A`], _rational, _dAlembert]

\begin{align*} \left (x -\sqrt {x^{2}+y^{2}}\right ) y^{\prime }&=y \end{align*}
Maple. Time used: 0.090 (sec). Leaf size: 18
ode:=(x-(x^2+y(x)^2)^(1/2))*diff(y(x),x) = y(x); 
dsolve(ode,y(x), singsol=all);
 
\[ -c_1 +\sqrt {x^{2}+y^{2}}+x = 0 \]
Mathematica. Time used: 0.271 (sec). Leaf size: 57
ode=(x-Sqrt[x^2+y[x]^2])*D[y[x],x]==y[x]; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 
\begin{align*} y(x)&\to -e^{\frac {c_1}{2}} \sqrt {-2 x+e^{c_1}}\\ y(x)&\to e^{\frac {c_1}{2}} \sqrt {-2 x+e^{c_1}}\\ y(x)&\to 0 \end{align*}
Sympy. Time used: 1.434 (sec). Leaf size: 12
from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq((x - sqrt(x**2 + y(x)**2))*Derivative(y(x), x) - y(x),0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 
\[ \log {\left (y{\left (x \right )} \right )} = C_{1} - \operatorname {asinh}{\left (\frac {x}{y{\left (x \right )}} \right )} \]