2.2.39 Problem 42
Internal
problem
ID
[13245]
Book
:
Handbook
of
exact
solutions
for
ordinary
differential
equations.
By
Polyanin
and
Zaitsev.
Second
edition
Section
:
Chapter
1,
section
1.2.
Riccati
Equation.
1.2.2.
Equations
Containing
Power
Functions
Problem
number
:
42
Date
solved
:
Wednesday, December 31, 2025 at 12:23:44 PM
CAS
classification
:
[_rational, _Riccati]
2.2.39.1 Solved using first_order_ode_riccati
10.231 (sec)
Entering first order ode riccati solver
\begin{align*}
y^{\prime } x&=a \,x^{n} y^{2}+y b +c \,x^{m} \\
\end{align*}
In canonical form the ODE is \begin{align*} y' &= F(x,y)\\ &= \frac {a \,x^{n} y^{2}+y b +c \,x^{m}}{x} \end{align*}
This is a Riccati ODE. Comparing the ODE to solve
\[
y' = \textit {the\_rhs}
\]
With Riccati ODE standard form \[ y' = f_0(x)+ f_1(x)y+f_2(x)y^{2} \]
Shows
that \(f_0(x)=\frac {c \,x^{m}}{x}\), \(f_1(x)=\frac {b}{x}\) and \(f_2(x)=\frac {a \,x^{n}}{x}\). Let \begin{align*} y &= \frac {-u'}{f_2 u} \\ &= \frac {-u'}{\frac {u a \,x^{n}}{x}} \tag {1} \end{align*}
Using the above substitution in the given ODE results (after some simplification) in a second
order ODE to solve for \(u(x)\) which is
\begin{align*} f_2 u''(x) -\left ( f_2' + f_1 f_2 \right ) u'(x) + f_2^2 f_0 u(x) &= 0 \tag {2} \end{align*}
But
\begin{align*} f_2' &=\frac {a \,x^{n} n}{x^{2}}-\frac {a \,x^{n}}{x^{2}}\\ f_1 f_2 &=\frac {b a \,x^{n}}{x^{2}}\\ f_2^2 f_0 &=\frac {a^{2} x^{2 n} c \,x^{m}}{x^{3}} \end{align*}
Substituting the above terms back in equation (2) gives
\[
\frac {a \,x^{n} u^{\prime \prime }\left (x \right )}{x}-\left (\frac {a \,x^{n} n}{x^{2}}-\frac {a \,x^{n}}{x^{2}}+\frac {b a \,x^{n}}{x^{2}}\right ) u^{\prime }\left (x \right )+\frac {a^{2} x^{2 n} c \,x^{m} u \left (x \right )}{x^{3}} = 0
\]
Unable to solve. Will ask Maple to solve
this ode now.
The solution for \(u \left (x \right )\) is
\begin{equation}
\tag{3} u \left (x \right ) = c_1 \,x^{\frac {b}{2}+\frac {n}{2}} \operatorname {BesselJ}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )+c_2 \,x^{\frac {b}{2}+\frac {n}{2}} \operatorname {BesselY}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )
\end{equation}
Taking derivative gives \begin{equation}
\tag{4} u^{\prime }\left (x \right ) = \frac {c_1 \,x^{\frac {b}{2}+\frac {n}{2}} \left (\frac {b}{2}+\frac {n}{2}\right ) \operatorname {BesselJ}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )}{x}+\frac {2 c_1 \,x^{\frac {b}{2}+\frac {n}{2}} \left (-\operatorname {BesselJ}\left (\frac {-b -n}{m +n}+1, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )+\frac {\left (-b -n \right ) x^{-\frac {m}{2}-\frac {n}{2}} \operatorname {BesselJ}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )}{2 \sqrt {a c}}\right ) \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}} \left (\frac {m}{2}+\frac {n}{2}\right )}{x \left (m +n \right )}+\frac {c_2 \,x^{\frac {b}{2}+\frac {n}{2}} \left (\frac {b}{2}+\frac {n}{2}\right ) \operatorname {BesselY}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )}{x}+\frac {2 c_2 \,x^{\frac {b}{2}+\frac {n}{2}} \left (-\operatorname {BesselY}\left (\frac {-b -n}{m +n}+1, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )+\frac {\left (-b -n \right ) x^{-\frac {m}{2}-\frac {n}{2}} \operatorname {BesselY}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )}{2 \sqrt {a c}}\right ) \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}} \left (\frac {m}{2}+\frac {n}{2}\right )}{x \left (m +n \right )}
\end{equation}
Substituting equations (3,4) into (1) results in \begin{align*}
y &= \frac {-u'}{f_2 u} \\
y &= \frac {-u'}{\frac {u a \,x^{n}}{x}} \\
y &= -\frac {\left (\frac {c_1 \,x^{\frac {b}{2}+\frac {n}{2}} \left (\frac {b}{2}+\frac {n}{2}\right ) \operatorname {BesselJ}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )}{x}+\frac {2 c_1 \,x^{\frac {b}{2}+\frac {n}{2}} \left (-\operatorname {BesselJ}\left (\frac {-b -n}{m +n}+1, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )+\frac {\left (-b -n \right ) x^{-\frac {m}{2}-\frac {n}{2}} \operatorname {BesselJ}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )}{2 \sqrt {a c}}\right ) \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}} \left (\frac {m}{2}+\frac {n}{2}\right )}{x \left (m +n \right )}+\frac {c_2 \,x^{\frac {b}{2}+\frac {n}{2}} \left (\frac {b}{2}+\frac {n}{2}\right ) \operatorname {BesselY}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )}{x}+\frac {2 c_2 \,x^{\frac {b}{2}+\frac {n}{2}} \left (-\operatorname {BesselY}\left (\frac {-b -n}{m +n}+1, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )+\frac {\left (-b -n \right ) x^{-\frac {m}{2}-\frac {n}{2}} \operatorname {BesselY}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )}{2 \sqrt {a c}}\right ) \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}} \left (\frac {m}{2}+\frac {n}{2}\right )}{x \left (m +n \right )}\right ) x^{-n} x}{a \left (c_1 \,x^{\frac {b}{2}+\frac {n}{2}} \operatorname {BesselJ}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )+c_2 \,x^{\frac {b}{2}+\frac {n}{2}} \operatorname {BesselY}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )\right )} \\
\end{align*}
Doing change of constants, the above solution becomes \[
y = -\frac {\left (\frac {x^{\frac {b}{2}+\frac {n}{2}} \left (\frac {b}{2}+\frac {n}{2}\right ) \operatorname {BesselJ}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )}{x}+\frac {2 x^{\frac {b}{2}+\frac {n}{2}} \left (-\operatorname {BesselJ}\left (\frac {-b -n}{m +n}+1, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )+\frac {\left (-b -n \right ) x^{-\frac {m}{2}-\frac {n}{2}} \operatorname {BesselJ}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )}{2 \sqrt {a c}}\right ) \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}} \left (\frac {m}{2}+\frac {n}{2}\right )}{x \left (m +n \right )}+\frac {c_3 \,x^{\frac {b}{2}+\frac {n}{2}} \left (\frac {b}{2}+\frac {n}{2}\right ) \operatorname {BesselY}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )}{x}+\frac {2 c_3 \,x^{\frac {b}{2}+\frac {n}{2}} \left (-\operatorname {BesselY}\left (\frac {-b -n}{m +n}+1, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )+\frac {\left (-b -n \right ) x^{-\frac {m}{2}-\frac {n}{2}} \operatorname {BesselY}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )}{2 \sqrt {a c}}\right ) \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}} \left (\frac {m}{2}+\frac {n}{2}\right )}{x \left (m +n \right )}\right ) x^{-n} x}{a \left (x^{\frac {b}{2}+\frac {n}{2}} \operatorname {BesselJ}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )+c_3 \,x^{\frac {b}{2}+\frac {n}{2}} \operatorname {BesselY}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )\right )}
\]
Simplifying the above gives
\begin{align*}
y &= \frac {x^{-\frac {n}{2}+\frac {m}{2}} \sqrt {a c}\, \left (\operatorname {BesselY}\left (\frac {-b +m}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right ) c_3 +\operatorname {BesselJ}\left (\frac {-b +m}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )\right )}{a \left (c_3 \operatorname {BesselY}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )+\operatorname {BesselJ}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )\right )} \\
\end{align*}
Summary of solutions found
\begin{align*}
y &= \frac {x^{-\frac {n}{2}+\frac {m}{2}} \sqrt {a c}\, \left (\operatorname {BesselY}\left (\frac {-b +m}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right ) c_3 +\operatorname {BesselJ}\left (\frac {-b +m}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )\right )}{a \left (c_3 \operatorname {BesselY}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )+\operatorname {BesselJ}\left (\frac {-b -n}{m +n}, \frac {2 \sqrt {a c}\, x^{\frac {m}{2}+\frac {n}{2}}}{m +n}\right )\right )} \\
\end{align*}
2.2.39.2 ✓ Maple. Time used: 0.003 (sec). Leaf size: 166
ode:=x*diff(y(x),x) = a*x^n*y(x)^2+b*y(x)+c*x^m;
dsolve(ode,y(x), singsol=all);
\[
y = \frac {x^{-\frac {n}{2}+\frac {m}{2}} \sqrt {a c}\, \left (\operatorname {BesselY}\left (\frac {-b +m}{n +m}, \frac {2 \sqrt {a c}\, x^{\frac {n}{2}+\frac {m}{2}}}{n +m}\right ) c_1 +\operatorname {BesselJ}\left (\frac {-b +m}{n +m}, \frac {2 \sqrt {a c}\, x^{\frac {n}{2}+\frac {m}{2}}}{n +m}\right )\right )}{a \left (\operatorname {BesselY}\left (\frac {-b -n}{n +m}, \frac {2 \sqrt {a c}\, x^{\frac {n}{2}+\frac {m}{2}}}{n +m}\right ) c_1 +\operatorname {BesselJ}\left (\frac {-b -n}{n +m}, \frac {2 \sqrt {a c}\, x^{\frac {n}{2}+\frac {m}{2}}}{n +m}\right )\right )}
\]
Maple trace
Methods for first order ODEs:
--- Trying classification methods ---
trying a quadrature
trying 1st order linear
trying Bernoulli
trying separable
trying inverse linear
trying homogeneous types:
trying Chini
differential order: 1; looking for linear symmetries
trying exact
Looking for potential symmetries
trying Riccati
trying Riccati sub-methods:
trying Riccati_symmetries
trying Riccati to 2nd Order
-> Calling odsolve with the ODE, diff(diff(y(x),x),x) = (b-1+n)/x*diff(y(x),
x)-x^(-1+n)*a*x^(-1+m)*c*y(x), y(x)
*** Sublevel 2 ***
Methods for second order ODEs:
--- Trying classification methods ---
trying a symmetry of the form [xi=0, eta=F(x)]
checking if the LODE is missing y
-> Trying an equivalence, under non-integer power transformations,
to LODEs admitting Liouvillian solutions.
-> Trying a Liouvillian solution using Kovacics algorithm
<- No Liouvillian solutions exists
-> Trying a solution in terms of special functions:
-> Bessel
<- Bessel successful
<- special function solution successful
<- Riccati to 2nd Order successful
Maple step by step
\[ \begin {array}{lll} & {} & \textrm {Let's solve}\hspace {3pt} \\ {} & {} & x \left (\frac {d}{d x}y \left (x \right )\right )=a \,x^{13245} y \left (x \right )^{2}+b y \left (x \right )+c \,x^{m} \\ \bullet & {} & \textrm {Highest derivative means the order of the ODE is}\hspace {3pt} 1 \\ {} & {} & \frac {d}{d x}y \left (x \right ) \\ \bullet & {} & \textrm {Solve for the highest derivative}\hspace {3pt} \\ {} & {} & \frac {d}{d x}y \left (x \right )=\frac {a \,x^{13245} y \left (x \right )^{2}+b y \left (x \right )+c \,x^{m}}{x} \end {array} \]
2.2.39.3 ✓ Mathematica. Time used: 0.48 (sec). Leaf size: 1321
ode=x*D[y[x],x]==a*x^(n)*y[x]^2+b*y[x]+c*x^(m);
ic={};
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
\begin{align*} \text {Solution too large to show}\end{align*}
2.2.39.4 ✗ Sympy
from sympy import *
x = symbols("x")
a = symbols("a")
b = symbols("b")
c = symbols("c")
m = symbols("m")
n = symbols("n")
y = Function("y")
ode = Eq(-a*x**n*y(x)**2 - b*y(x) - c*x**m + x*Derivative(y(x), x),0)
ics = {}
dsolve(ode,func=y(x),ics=ics)
NotImplementedError : The given ODE Derivative(y(x), x) - (a*x**n*y(x)**2 + b*y(x) + c*x**m)/x cannot be solved by the factorable group method