60.1.52 problem 53

Internal problem ID [10066]
Book : Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section : Chapter 1, linear first order
Problem number : 53
Date solved : Sunday, March 30, 2025 at 02:59:40 PM
CAS classification : [_Chini, [_1st_order, `_with_symmetry_[F(x),G(x)*y+H(x)]`]]

\begin{align*} y^{\prime }-f \left (x \right )^{1-n} g^{\prime }\left (x \right ) y^{n} \left (a g \left (x \right )+b \right )^{-n}-\frac {f^{\prime }\left (x \right ) y}{f \left (x \right )}-f \left (x \right ) g^{\prime }\left (x \right )&=0 \end{align*}

Maple. Time used: 0.011 (sec). Leaf size: 215
ode:=diff(y(x),x)-f(x)^(-n+1)*diff(g(x),x)*y(x)^n/((a*g(x)+b)^n)-diff(f(x),x)*y(x)/f(x)-f(x)*diff(g(x),x) = 0; 
dsolve(ode,y(x), singsol=all);
 
\[ y = \frac {\operatorname {RootOf}\left (\left (n a f \left (x \right )^{2-n} {g^{\prime }\left (x \right )}^{3} \left (a g \left (x \right )+b \right )^{-n -1}\right )^{n} f \left (x \right )^{n} \left (a g \left (x \right )+b \right )^{n} \int _{}^{\textit {\_Z}}-\frac {1}{\textit {\_a} f \left (x \right )^{n} \left (a g \left (x \right )+b \right )^{n} \left (n a f \left (x \right )^{2-n} {g^{\prime }\left (x \right )}^{3} \left (a g \left (x \right )+b \right )^{-n -1}\right )^{n}-\textit {\_a}^{n} \left (f \left (x \right )^{1-n} g^{\prime }\left (x \right ) \left (a g \left (x \right )+b \right )^{-n}\right )^{n} \left (f \left (x \right ) g^{\prime }\left (x \right )\right )^{2 n} n^{n}-\left (n a f \left (x \right )^{2-n} {g^{\prime }\left (x \right )}^{3} \left (a g \left (x \right )+b \right )^{-n -1}\right )^{n} f \left (x \right )^{n} \left (a g \left (x \right )+b \right )^{n}}d \textit {\_a} -\ln \left (a g \left (x \right )+b \right )+c_1 \right ) \left (a g \left (x \right )+b \right ) f \left (x \right )}{a} \]
Mathematica. Time used: 0.907 (sec). Leaf size: 96
ode=D[y[x],x] - f[x]^(1-n)*D[ g[x],x]*y[x]^n/(a*g[x]+b)^n - D[ f[x],x]*y[x]/f[x] - f[x]*D[ g[x],x]==0; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 
\[ \text {Solve}\left [\int _1^{\left (f(x)^{-n} (b+a g(x))^{-n}\right )^{\frac {1}{n}} y(x)}\frac {1}{K[1]^n-\left (a^n\right )^{\frac {1}{n}} K[1]+1}dK[1]=\frac {f(x) (a g(x)+b) \log (a g(x)+b) \left (f(x)^{-n} (a g(x)+b)^{-n}\right )^{\frac {1}{n}}}{a}+c_1,y(x)\right ] \]
Sympy
from sympy import * 
x = symbols("x") 
a = symbols("a") 
b = symbols("b") 
n = symbols("n") 
y = Function("y") 
f = Function("f") 
g = Function("g") 
ode = Eq(-f(x)*Derivative(g(x), x) + Derivative(y(x), x) - y(x)*Derivative(f(x), x)/f(x) - f(x)**(1 - n)*y(x)**n*Derivative(g(x), x)/(a*g(x) + b)**n,0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 
RecursionError : maximum recursion depth exceeded