56.1.38 problem 39

Internal problem ID [8750]
Book : Own collection of miscellaneous problems
Section : section 1.0
Problem number : 39
Date solved : Sunday, March 30, 2025 at 01:30:12 PM
CAS classification : [_rational, _Riccati]

\begin{align*} u^{\prime }+u^{2}&=\frac {1}{x^{{4}/{5}}} \end{align*}

Maple. Time used: 0.002 (sec). Leaf size: 46
ode:=diff(u(x),x)+u(x)^2 = 1/x^(4/5); 
dsolve(ode,u(x), singsol=all);
 
\[ u = \frac {\operatorname {BesselI}\left (-\frac {1}{6}, \frac {5 x^{{3}/{5}}}{3}\right ) c_1 -\operatorname {BesselK}\left (\frac {1}{6}, \frac {5 x^{{3}/{5}}}{3}\right )}{x^{{2}/{5}} \left (c_1 \operatorname {BesselI}\left (\frac {5}{6}, \frac {5 x^{{3}/{5}}}{3}\right )+\operatorname {BesselK}\left (\frac {5}{6}, \frac {5 x^{{3}/{5}}}{3}\right )\right )} \]
Mathematica. Time used: 0.274 (sec). Leaf size: 286
ode=D[u[x],x]+u[x]^2==x^(-4/5); 
ic={}; 
DSolve[{ode,ic},u[x],x,IncludeSingularSolutions->True]
 
\begin{align*} u(x)\to \frac {(-1)^{5/6} x^{3/5} \operatorname {Gamma}\left (\frac {11}{6}\right ) \operatorname {BesselI}\left (-\frac {1}{6},\frac {5 x^{3/5}}{3}\right )+(-1)^{5/6} \operatorname {Gamma}\left (\frac {11}{6}\right ) \operatorname {BesselI}\left (\frac {5}{6},\frac {5 x^{3/5}}{3}\right )+(-1)^{5/6} x^{3/5} \operatorname {Gamma}\left (\frac {11}{6}\right ) \operatorname {BesselI}\left (\frac {11}{6},\frac {5 x^{3/5}}{3}\right )+c_1 x^{3/5} \operatorname {Gamma}\left (\frac {1}{6}\right ) \operatorname {BesselI}\left (-\frac {11}{6},\frac {5 x^{3/5}}{3}\right )+c_1 \operatorname {Gamma}\left (\frac {1}{6}\right ) \operatorname {BesselI}\left (-\frac {5}{6},\frac {5 x^{3/5}}{3}\right )+c_1 x^{3/5} \operatorname {Gamma}\left (\frac {1}{6}\right ) \operatorname {BesselI}\left (\frac {1}{6},\frac {5 x^{3/5}}{3}\right )}{2 x \left ((-1)^{5/6} \operatorname {Gamma}\left (\frac {11}{6}\right ) \operatorname {BesselI}\left (\frac {5}{6},\frac {5 x^{3/5}}{3}\right )+c_1 \operatorname {Gamma}\left (\frac {1}{6}\right ) \operatorname {BesselI}\left (-\frac {5}{6},\frac {5 x^{3/5}}{3}\right )\right )} \\ u(x)\to \frac {x^{3/5} \operatorname {BesselI}\left (-\frac {11}{6},\frac {5 x^{3/5}}{3}\right )+\operatorname {BesselI}\left (-\frac {5}{6},\frac {5 x^{3/5}}{3}\right )+x^{3/5} \operatorname {BesselI}\left (\frac {1}{6},\frac {5 x^{3/5}}{3}\right )}{2 x \operatorname {BesselI}\left (-\frac {5}{6},\frac {5 x^{3/5}}{3}\right )} \\ \end{align*}
Sympy
from sympy import * 
x = symbols("x") 
u = Function("u") 
ode = Eq(u(x)**2 + Derivative(u(x), x) - 1/x**(4/5),0) 
ics = {} 
dsolve(ode,func=u(x),ics=ics)
 
NotImplementedError : The given ODE u(x)**2 + Derivative(u(x), x) - 1/x**(4/5) cannot be solved by the lie group method