31.9 problem 908

Internal problem ID [4144]

Book: Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section: Various 31
Problem number: 908.
ODE order: 1.
ODE degree: 2.

CAS Maple gives this as type [_separable]

\[ \boxed {x^{2} {y^{\prime }}^{2}-4 x \left (y+2\right ) y^{\prime }+4 \left (y+2\right ) y=0} \]

Solution by Maple

Time used: 0.062 (sec). Leaf size: 122

dsolve(x^2*diff(y(x),x)^2-4*x*(2+y(x))*diff(y(x),x)+4*(2+y(x))*y(x) = 0,y(x), singsol=all)
 

\begin{align*} y \left (x \right ) = -2 y \left (x \right ) = \frac {\left (-\frac {2 \sqrt {2}\, \sqrt {c_{1} x^{2}}}{x^{2}}+1\right ) x^{2}}{c_{1}} y \left (x \right ) = \frac {\left (\frac {2 \sqrt {2}\, \sqrt {c_{1} x^{2}}}{x^{2}}+1\right ) x^{2}}{c_{1}} y \left (x \right ) = -\frac {-2 c_{1} \left (-\sqrt {2}\, x +4 c_{1} \right )+8 c_{1}^{2}-x^{2}}{c_{1}^{2}} y \left (x \right ) = -\frac {-2 c_{1} \left (\sqrt {2}\, x +4 c_{1} \right )+8 c_{1}^{2}-x^{2}}{c_{1}^{2}} \end{align*}

Solution by Mathematica

Time used: 0.233 (sec). Leaf size: 69

DSolve[x^2 (y'[x])^2-4 x(2+y[x])y'[x]+4(2+y[x])y[x]==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to e^{-c_1} x \left (x-2 \sqrt {2} e^{\frac {c_1}{2}}\right ) y(x)\to e^{c_1} x^2-2 \sqrt {2} e^{\frac {c_1}{2}} x y(x)\to -2 y(x)\to 0 \end{align*}