1.493 problem 494

Internal problem ID [8074]

Book: Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section: Chapter 1, linear first order
Problem number: 494.
ODE order: 1.
ODE degree: 2.

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

Solve \begin {gather*} \boxed {\left (y^{2}-a^{2} x^{2}\right ) \left (y^{\prime }\right )^{2}+2 y y^{\prime } x +\left (-a^{2}+1\right ) x^{2}=0} \end {gather*}

Solution by Maple

Time used: 0.473 (sec). Leaf size: 154

dsolve((y(x)^2-a^2*x^2)*diff(y(x),x)^2+2*x*y(x)*diff(y(x),x)+(-a^2+1)*x^2 = 0,y(x), singsol=all)
 

\begin{align*} y \relax (x ) = \RootOf \left (-\ln \relax (x )+\int _{}^{\textit {\_Z}}\frac {-\textit {\_a}^{3}+\textit {\_a} \,a^{2}+\sqrt {\textit {\_a}^{2} a^{2}-a^{4}+a^{2}}-\textit {\_a}}{\textit {\_a}^{4}-\textit {\_a}^{2} a^{2}+2 \textit {\_a}^{2}-a^{2}+1}d \textit {\_a} +c_{1}\right ) x \\ y \relax (x ) = \RootOf \left (-\ln \relax (x )-\left (\int _{}^{\textit {\_Z}}\frac {\textit {\_a}^{3}-\textit {\_a} \,a^{2}+\sqrt {\textit {\_a}^{2} a^{2}-a^{4}+a^{2}}+\textit {\_a}}{\textit {\_a}^{4}-\textit {\_a}^{2} a^{2}+2 \textit {\_a}^{2}-a^{2}+1}d \textit {\_a} \right )+c_{1}\right ) x \\ y \relax (x ) = c_{1} x \\ \end{align*}

Solution by Mathematica

Time used: 0.242 (sec). Leaf size: 80

DSolve[(1 - a^2)*x^2 + 2*x*y[x]*y'[x] + (-(a^2*x^2) + y[x]^2)*y'[x]^2==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to a c_1-\sqrt {-x^2+c_1{}^2} \\ y(x)\to a c_1+\sqrt {-x^2+c_1{}^2} \\ y(x)\to -\sqrt {a^2-1} x \\ y(x)\to \sqrt {a^2-1} x \\ \end{align*}