60.7.210 problem 1801 (book 6.210)

Internal problem ID [11799]
Book : Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section : Chapter 6, non-linear second order
Problem number : 1801 (book 6.210)
Date solved : Monday, January 27, 2025 at 11:36:01 PM
CAS classification : [[_2nd_order, _missing_x], _Liouville, [_2nd_order, _reducible, _mu_x_y1], [_2nd_order, _reducible, _mu_xy]]

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

✓ Solution by Maple

Time used: 0.108 (sec). Leaf size: 78

dsolve(y(x)*(y(x)^2+1)*diff(diff(y(x),x),x)+(1-3*y(x)^2)*diff(y(x),x)^2=0,y(x), singsol=all)
 

\begin{align*} y &= -i \\ y &= i \\ y &= 0 \\ y &= -\frac {\sqrt {2}\, \sqrt {-2 \left (c_{1} x +c_{2} \right ) \left (c_{1} x +c_{2} +\frac {1}{2}\right )}}{2 c_{1} x +2 c_{2}} \\ y &= \frac {\sqrt {2}\, \sqrt {-2 \left (c_{1} x +c_{2} \right ) \left (c_{1} x +c_{2} +\frac {1}{2}\right )}}{2 c_{1} x +2 c_{2}} \\ \end{align*}

✓ Solution by Mathematica

Time used: 0.932 (sec). Leaf size: 171

DSolve[(1 - 3*y[x]^2)*D[y[x],x]^2 + y[x]*(1 + y[x]^2)*D[y[x],{x,2}] == 0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to \text {InverseFunction}\left [\int _1^{\text {$\#$1}}\frac {\exp \left (-\int _1^{K[2]}\frac {3 K[1]^2-1}{K[1] \left (K[1]^2+1\right )}dK[1]\right )}{c_1}dK[2]\&\right ][x+c_2] \\ y(x)\to \text {InverseFunction}\left [\int _1^{\text {$\#$1}}-\frac {\exp \left (-\int _1^{K[2]}\frac {3 K[1]^2-1}{K[1] \left (K[1]^2+1\right )}dK[1]\right )}{c_1}dK[2]\&\right ][x+c_2] \\ y(x)\to \text {InverseFunction}\left [\int _1^{\text {$\#$1}}\frac {\exp \left (-\int _1^{K[2]}\frac {3 K[1]^2-1}{K[1] \left (K[1]^2+1\right )}dK[1]\right )}{c_1}dK[2]\&\right ][x+c_2] \\ \end{align*}