83.23.25 problem 25

Internal problem ID [19235]
Book : A Text book for differentional equations for postgraduate students by Ray and Chaturvedi. First edition, 1958. BHASKAR press. INDIA
Section : Chapter V. Singular solutions. Exercise V at page 76
Problem number : 25
Date solved : Monday, March 31, 2025 at 07:00:26 PM
CAS classification : [[_1st_order, _with_linear_symmetries], _rational, _Clairaut]

\begin{align*} \left (a^{2}-x^{2}\right ) {y^{\prime }}^{2}+2 x y y^{\prime }+b^{2}-y^{2}&=0 \end{align*}

✓ Maple. Time used: 0.189 (sec). Leaf size: 82

ode:=(a^2-x^2)*diff(y(x),x)^2+2*x*y(x)*diff(y(x),x)+b^2-y(x)^2 = 0; 
dsolve(ode,y(x), singsol=all);
 

\begin{align*} y &= \frac {\sqrt {a^{2}-x^{2}}\, b}{a} \\ y &= -\frac {\sqrt {a^{2}-x^{2}}\, b}{a} \\ y &= c_1 x -\sqrt {c_1^{2} a^{2}+b^{2}} \\ y &= c_1 x +\sqrt {c_1^{2} a^{2}+b^{2}} \\ \end{align*}

✓ Mathematica. Time used: 2.816 (sec). Leaf size: 419

ode=(a^2-x^2)*D[y[x],x]^2+2*x*y[x]*D[y[x],x]+b^2-y[x]^2==0; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 

\begin{align*} \text {Solve}\left [-\frac {\sqrt {a^2 \left (y(x)^2-b^2\right )} \arctan \left (\frac {\sqrt {y(x)^2-b^2}}{b}\right )}{b \sqrt {y(x)^2-b^2}}-\frac {2 \sqrt {y(x)^2-b^2} \sqrt {-a^2 \left (b^2-y(x)^2\right )} \arctan \left (\frac {b x \sqrt {y(x)^2-b^2}}{y(x) \left (\sqrt {a^2 \left (y(x)^2-b^2\right )}-\sqrt {a^2 \left (y(x)^2-b^2\right )+b^2 x^2}\right )+b^2 x}\right )}{b^3-b y(x)^2}&=c_1,y(x)\right ] \\ \text {Solve}\left [\frac {\sqrt {a^2 \left (y(x)^2-b^2\right )} \arctan \left (\frac {\sqrt {y(x)^2-b^2}}{b}\right )}{b \sqrt {y(x)^2-b^2}}+\frac {2 \sqrt {y(x)^2-b^2} \sqrt {-a^2 \left (b^2-y(x)^2\right )} \arctan \left (\frac {b x \sqrt {y(x)^2-b^2}}{y(x) \left (\sqrt {a^2 \left (y(x)^2-b^2\right )+b^2 x^2}-\sqrt {a^2 \left (y(x)^2-b^2\right )}\right )+b^2 x}\right )}{b^3-b y(x)^2}&=c_1,y(x)\right ] \\ y(x)\to -\frac {b \sqrt {a^2-x^2}}{a} \\ y(x)\to \frac {b \sqrt {a^2-x^2}}{a} \\ \end{align*}

✗ Sympy

from sympy import * 
x = symbols("x") 
a = symbols("a") 
b = symbols("b") 
y = Function("y") 
ode = Eq(b**2 + 2*x*y(x)*Derivative(y(x), x) + (a**2 - x**2)*Derivative(y(x), x)**2 - y(x)**2,0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 

Timed Out