31.21 problem 920

Internal problem ID [3648]

Book: Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section: Various 31
Problem number: 920.
ODE order: 1.
ODE degree: 2.

CAS Maple gives this as type [[_1st_order, _with_symmetry_[F(x),G(y)]]]

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

Solution by Maple

Time used: 0.564 (sec). Leaf size: 37

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

\begin{align*} y \relax (x ) = c_{1} x^{2}-c_{1} a^{2}-\frac {1}{4 c_{1}} \\ y \relax (x ) = c_{1} \sqrt {-a^{2}+x^{2}} \\ \end{align*}

Solution by Mathematica

Time used: 0.431 (sec). Leaf size: 67

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

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