9.19.14 problem 14

Internal problem ID [3298]
Book : Differential Equations by Alfred L. Nelson, Karl W. Folley, Max Coral. 3rd ed. DC heath. Boston. 1964
Section : Exercise 37, page 171
Problem number : 14
Date solved : Tuesday, September 30, 2025 at 06:32:58 AM
CAS classification : [[_homogeneous, `class A`], _rational, _dAlembert]

\begin{align*} y {y^{\prime }}^{2}-2 x y^{\prime }+y&=0 \end{align*}
Maple. Time used: 0.318 (sec). Leaf size: 67
ode:=y(x)*diff(y(x),x)^2-2*x*diff(y(x),x)+y(x) = 0; 
dsolve(ode,y(x), singsol=all);
 
\begin{align*} y &= -x \\ y &= x \\ y &= 0 \\ y &= \sqrt {c_1 \left (-2 i x +c_1 \right )} \\ y &= \sqrt {c_1 \left (2 i x +c_1 \right )} \\ y &= -\sqrt {c_1 \left (-2 i x +c_1 \right )} \\ y &= -\sqrt {c_1 \left (2 i x +c_1 \right )} \\ \end{align*}
Mathematica. Time used: 0.747 (sec). Leaf size: 64
ode=y[x]*D[y[x],x]^2-2*x*D[y[x],x]+y[x]==0; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 
\begin{align*} y(x)&\to -\sqrt {-e^{c_1} \left (-2 x+e^{c_1}\right )}\\ y(x)&\to \sqrt {-e^{c_1} \left (-2 x+e^{c_1}\right )}\\ y(x)&\to 0\\ y(x)&\to -x\\ y(x)&\to x \end{align*}
Sympy. Time used: 168.867 (sec). Leaf size: 469
from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(-2*x*Derivative(y(x), x) + y(x)*Derivative(y(x), x)**2 + y(x),0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 
\[ \left [ y{\left (x \right )} = - \frac {\sqrt {2} \sqrt {C_{1} - 2 \sqrt {2} x \sqrt {- C_{1}}}}{2}, \ y{\left (x \right )} = \frac {\sqrt {2} \sqrt {C_{1} - 2 \sqrt {2} x \sqrt {- C_{1}}}}{2}, \ y{\left (x \right )} = - \frac {\sqrt {2} \sqrt {C_{1} + 2 \sqrt {2} x \sqrt {- C_{1}}}}{2}, \ y{\left (x \right )} = \frac {\sqrt {2} \sqrt {C_{1} + 2 \sqrt {2} x \sqrt {- C_{1}}}}{2}, \ y{\left (x \right )} = - \frac {\sqrt {2} \sqrt {- 2 \sqrt {2} \sqrt {C_{1}} x - C_{1}}}{2}, \ y{\left (x \right )} = \frac {\sqrt {2} \sqrt {- 2 \sqrt {2} \sqrt {C_{1}} x - C_{1}}}{2}, \ y{\left (x \right )} = - \frac {\sqrt {2} \sqrt {2 \sqrt {2} \sqrt {C_{1}} x - C_{1}}}{2}, \ y{\left (x \right )} = \frac {\sqrt {2} \sqrt {2 \sqrt {2} \sqrt {C_{1}} x - C_{1}}}{2}, \ y{\left (x \right )} = - \frac {\sqrt {2} \sqrt {C_{1} - 2 \sqrt {2} x \sqrt {- C_{1}}}}{2}, \ y{\left (x \right )} = \frac {\sqrt {2} \sqrt {C_{1} - 2 \sqrt {2} x \sqrt {- C_{1}}}}{2}, \ y{\left (x \right )} = - \frac {\sqrt {2} \sqrt {C_{1} + 2 \sqrt {2} x \sqrt {- C_{1}}}}{2}, \ y{\left (x \right )} = \frac {\sqrt {2} \sqrt {C_{1} + 2 \sqrt {2} x \sqrt {- C_{1}}}}{2}, \ y{\left (x \right )} = - \frac {\sqrt {2} \sqrt {- 2 \sqrt {2} \sqrt {C_{1}} x - C_{1}}}{2}, \ y{\left (x \right )} = \frac {\sqrt {2} \sqrt {- 2 \sqrt {2} \sqrt {C_{1}} x - C_{1}}}{2}, \ y{\left (x \right )} = - \frac {\sqrt {2} \sqrt {2 \sqrt {2} \sqrt {C_{1}} x - C_{1}}}{2}, \ y{\left (x \right )} = \frac {\sqrt {2} \sqrt {2 \sqrt {2} \sqrt {C_{1}} x - C_{1}}}{2}\right ] \]