60.1.536 problem 549

Internal problem ID [10550]
Book : Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section : Chapter 1, linear first order
Problem number : 549
Date solved : Sunday, March 30, 2025 at 05:59:58 PM
CAS classification : [_quadrature]

\begin{align*} x^{2} \left ({y^{\prime }}^{2}+1\right )^{3}-a^{2}&=0 \end{align*}

Maple. Time used: 0.055 (sec). Leaf size: 581
ode:=x^2*(1+diff(y(x),x)^2)^3-a^2 = 0; 
dsolve(ode,y(x), singsol=all);
 
\begin{align*} \text {Solution too large to show}\end{align*}

Mathematica. Time used: 0.116 (sec). Leaf size: 216
ode=-a^2 + x^2*(1 + D[y[x],x]^2)^3==0; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 
\begin{align*} y(x)\to -x \left (\frac {a^{2/3}}{x^{2/3}}-1\right )^{3/2}+c_1 \\ y(x)\to x \left (\frac {a^{2/3}}{x^{2/3}}-1\right )^{3/2}+c_1 \\ y(x)\to c_1-x \left (-1-\frac {i \left (\sqrt {3}-i\right ) a^{2/3}}{2 x^{2/3}}\right )^{3/2} \\ y(x)\to x \left (-1-\frac {i \left (\sqrt {3}-i\right ) a^{2/3}}{2 x^{2/3}}\right )^{3/2}+c_1 \\ y(x)\to c_1-x \left (-1+\frac {i \left (\sqrt {3}+i\right ) a^{2/3}}{2 x^{2/3}}\right )^{3/2} \\ y(x)\to x \left (-1+\frac {i \left (\sqrt {3}+i\right ) a^{2/3}}{2 x^{2/3}}\right )^{3/2}+c_1 \\ \end{align*}
Sympy. Time used: 4.325 (sec). Leaf size: 221
from sympy import * 
x = symbols("x") 
a = symbols("a") 
y = Function("y") 
ode = Eq(-a**2 + x**2*(Derivative(y(x), x)**2 + 1)**3,0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 
\[ \left [ y{\left (x \right )} = C_{1} - \int \sqrt {\sqrt [3]{\frac {a^{2}}{x^{2}}} - 1}\, dx, \ y{\left (x \right )} = C_{1} + \int \sqrt {\sqrt [3]{\frac {a^{2}}{x^{2}}} - 1}\, dx, \ y{\left (x \right )} = C_{1} - \frac {\sqrt {2} \int \sqrt {- \sqrt [3]{\frac {a^{2}}{x^{2}}} - \sqrt {3} i \sqrt [3]{\frac {a^{2}}{x^{2}}} - 2}\, dx}{2}, \ y{\left (x \right )} = C_{1} + \frac {\sqrt {2} \int \sqrt {- \sqrt [3]{\frac {a^{2}}{x^{2}}} - \sqrt {3} i \sqrt [3]{\frac {a^{2}}{x^{2}}} - 2}\, dx}{2}, \ y{\left (x \right )} = C_{1} - \frac {\sqrt {2} \int \sqrt {- \sqrt [3]{\frac {a^{2}}{x^{2}}} + \sqrt {3} i \sqrt [3]{\frac {a^{2}}{x^{2}}} - 2}\, dx}{2}, \ y{\left (x \right )} = C_{1} + \frac {\sqrt {2} \int \sqrt {- \sqrt [3]{\frac {a^{2}}{x^{2}}} + \sqrt {3} i \sqrt [3]{\frac {a^{2}}{x^{2}}} - 2}\, dx}{2}\right ] \]