60.7.171 problem 1791 (book 6.200)
Internal
problem
ID
[11721]
Book
:
Differential
Gleichungen,
E.
Kamke,
3rd
ed.
Chelsea
Pub.
NY,
1948
Section
:
Chapter
6,
non-linear
second
order
Problem
number
:
1791
(book
6.200)
Date
solved
:
Wednesday, March 05, 2025 at 02:42:38 PM
CAS
classification
:
[[_2nd_order, _missing_x]]
\begin{align*} 3 y \left (1-y\right ) y^{\prime \prime }-2 \left (1-2 y\right ) {y^{\prime }}^{2}-h \left (y\right )&=0 \end{align*}
✓ Maple. Time used: 0.023 (sec). Leaf size: 120
ode:=3*y(x)*(1-y(x))*diff(diff(y(x),x),x)-2*(-2*y(x)+1)*diff(y(x),x)^2-h(y(x)) = 0;
dsolve(ode,y(x), singsol=all);
\begin{align*}
-\sqrt {3}\, \left (\int _{}^{y}\frac {1}{\sqrt {-\left (\textit {\_b} \left (\textit {\_b} -1\right )\right )^{{1}/{3}} \textit {\_b} \left (\textit {\_b} -1\right ) \left (2 \left (\int \frac {h \left (\textit {\_b} \right )}{\textit {\_b}^{2} \left (\textit {\_b} -1\right )^{2} \left (\textit {\_b} \left (\textit {\_b} -1\right )\right )^{{1}/{3}}}d \textit {\_b} \right )-3 c_{1} \right )}}d \textit {\_b} \right )-x -c_{2} &= 0 \\
\sqrt {3}\, \left (\int _{}^{y}\frac {1}{\sqrt {-\left (\textit {\_b} \left (\textit {\_b} -1\right )\right )^{{1}/{3}} \textit {\_b} \left (\textit {\_b} -1\right ) \left (2 \left (\int \frac {h \left (\textit {\_b} \right )}{\textit {\_b}^{2} \left (\textit {\_b} -1\right )^{2} \left (\textit {\_b} \left (\textit {\_b} -1\right )\right )^{{1}/{3}}}d \textit {\_b} \right )-3 c_{1} \right )}}d \textit {\_b} \right )-x -c_{2} &= 0 \\
\end{align*}
✓ Mathematica. Time used: 1.058 (sec). Leaf size: 710
ode=-h[y[x]] - 2*(1 - 2*y[x])*D[y[x],x]^2 + 3*(1 - y[x])*y[x]*D[y[x],{x,2}] == 0;
ic={};
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
\begin{align*}
y(x)\to \text {InverseFunction}\left [\int _1^{\text {$\#$1}}-\frac {\exp \left (-\int _1^{K[3]}\frac {4 K[1]-2}{3 (K[1]-1) K[1]}dK[1]\right )}{\sqrt {c_1+2 \int _1^{K[3]}-\frac {\exp \left (-2 \int _1^{K[2]}\frac {4 K[1]-2}{3 (K[1]-1) K[1]}dK[1]\right ) h(K[2])}{3 (K[2]-1) K[2]}dK[2]}}dK[3]\&\right ][x+c_2] \\
y(x)\to \text {InverseFunction}\left [\int _1^{\text {$\#$1}}\frac {\exp \left (-\int _1^{K[4]}\frac {4 K[1]-2}{3 (K[1]-1) K[1]}dK[1]\right )}{\sqrt {c_1+2 \int _1^{K[4]}-\frac {\exp \left (-2 \int _1^{K[2]}\frac {4 K[1]-2}{3 (K[1]-1) K[1]}dK[1]\right ) h(K[2])}{3 (K[2]-1) K[2]}dK[2]}}dK[4]\&\right ][x+c_2] \\
y(x)\to \text {InverseFunction}\left [\int _1^{\text {$\#$1}}-\frac {\exp \left (-\int _1^{K[3]}\frac {4 K[1]-2}{3 (K[1]-1) K[1]}dK[1]\right )}{\sqrt {2 \int _1^{K[3]}-\frac {\exp \left (-2 \int _1^{K[2]}\frac {4 K[1]-2}{3 (K[1]-1) K[1]}dK[1]\right ) h(K[2])}{3 (K[2]-1) K[2]}dK[2]-c_1}}dK[3]\&\right ][x+c_2] \\
y(x)\to \text {InverseFunction}\left [\int _1^{\text {$\#$1}}-\frac {\exp \left (-\int _1^{K[3]}\frac {4 K[1]-2}{3 (K[1]-1) K[1]}dK[1]\right )}{\sqrt {c_1+2 \int _1^{K[3]}-\frac {\exp \left (-2 \int _1^{K[2]}\frac {4 K[1]-2}{3 (K[1]-1) K[1]}dK[1]\right ) h(K[2])}{3 (K[2]-1) K[2]}dK[2]}}dK[3]\&\right ][x+c_2] \\
y(x)\to \text {InverseFunction}\left [\int _1^{\text {$\#$1}}\frac {\exp \left (-\int _1^{K[4]}\frac {4 K[1]-2}{3 (K[1]-1) K[1]}dK[1]\right )}{\sqrt {2 \int _1^{K[4]}-\frac {\exp \left (-2 \int _1^{K[2]}\frac {4 K[1]-2}{3 (K[1]-1) K[1]}dK[1]\right ) h(K[2])}{3 (K[2]-1) K[2]}dK[2]-c_1}}dK[4]\&\right ][x+c_2] \\
y(x)\to \text {InverseFunction}\left [\int _1^{\text {$\#$1}}\frac {\exp \left (-\int _1^{K[4]}\frac {4 K[1]-2}{3 (K[1]-1) K[1]}dK[1]\right )}{\sqrt {c_1+2 \int _1^{K[4]}-\frac {\exp \left (-2 \int _1^{K[2]}\frac {4 K[1]-2}{3 (K[1]-1) K[1]}dK[1]\right ) h(K[2])}{3 (K[2]-1) K[2]}dK[2]}}dK[4]\&\right ][x+c_2] \\
\end{align*}
✗ Sympy
from sympy import *
x = symbols("x")
y = Function("y")
h = Function("h")
ode = Eq((3 - 3*y(x))*y(x)*Derivative(y(x), (x, 2)) + (4*y(x) - 2)*Derivative(y(x), x)**2 - h(y(x)),0)
ics = {}
dsolve(ode,func=y(x),ics=ics)
NotImplementedError : The given ODE -sqrt(2)*sqrt((h(y(x)) + 3*y(x)**2*Derivative(y(x), (x, 2)) - 3*y(x)*Derivative(y(x), (x, 2)))/(2*y(x) - 1))/2 + Derivative(y(x), x) cannot be solved by the factorable group method