21.22 problem 598

Internal problem ID [3848]

Book: Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section: Various 21
Problem number: 598.
ODE order: 1.
ODE degree: 1.

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

\[ \boxed {\left (x^{2}+y^{2}\right ) y^{\prime }+y x=0} \]

Solution by Maple

Time used: 0.36 (sec). Leaf size: 223

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

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

Solution by Mathematica

Time used: 13.959 (sec). Leaf size: 218

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

\begin{align*} y(x)\to -\sqrt {-x^2-\sqrt {x^4+e^{4 c_1}}} y(x)\to \sqrt {-x^2-\sqrt {x^4+e^{4 c_1}}} y(x)\to -\sqrt {-x^2+\sqrt {x^4+e^{4 c_1}}} y(x)\to \sqrt {-x^2+\sqrt {x^4+e^{4 c_1}}} y(x)\to 0 y(x)\to -\sqrt {-\sqrt {x^4}-x^2} y(x)\to \sqrt {-\sqrt {x^4}-x^2} y(x)\to -\sqrt {\sqrt {x^4}-x^2} y(x)\to \sqrt {\sqrt {x^4}-x^2} \end{align*}