2.13.8 Problem 57
Internal
problem
ID
[13416]
Book
:
Handbook
of
exact
solutions
for
ordinary
differential
equations.
By
Polyanin
and
Zaitsev.
Second
edition
Section
:
Chapter
1,
section
1.2.
Riccati
Equation.
subsection
1.2.6-5.
Equations
containing
combinations
of
trigonometric
functions.
Problem
number
:
57
Date
solved
:
Sunday, January 18, 2026 at 08:02:21 PM
CAS
classification
:
[_Riccati]
2.13.8.1 Solved using first_order_ode_riccati
9.984 (sec)
Entering first order ode riccati solver
\begin{align*}
y^{\prime }&=y^{2}+a \lambda +b \lambda +2 a b +a \left (\lambda -a \right ) \tan \left (\lambda x \right )^{2}+b \left (\lambda -b \right ) \cot \left (\lambda x \right )^{2} \\
\end{align*}
In canonical form the ODE is \begin{align*} y' &= F(x,y)\\ &= -\tan \left (\lambda x \right )^{2} a^{2}+\tan \left (\lambda x \right )^{2} a \lambda -b^{2} \cot \left (\lambda x \right )^{2}+b \cot \left (\lambda x \right )^{2} \lambda +2 a b +a \lambda +b \lambda +y^{2} \end{align*}
This is a Riccati ODE. Comparing the ODE to solve
\[
y' = -\tan \left (\lambda x \right )^{2} a^{2}+\tan \left (\lambda x \right )^{2} a \lambda -b^{2} \cot \left (\lambda x \right )^{2}+b \cot \left (\lambda x \right )^{2} \lambda +2 a b +a \lambda +b \lambda +y^{2}
\]
With Riccati ODE standard form \[ y' = f_0(x)+ f_1(x)y+f_2(x)y^{2} \]
Shows
that \(f_0(x)=-\tan \left (\lambda x \right )^{2} a^{2}+\tan \left (\lambda x \right )^{2} a \lambda -b^{2} \cot \left (\lambda x \right )^{2}+b \cot \left (\lambda x \right )^{2} \lambda +2 a b +a \lambda +b \lambda \), \(f_1(x)=0\) and \(f_2(x)=1\). Let \begin{align*} y &= \frac {-u'}{f_2 u} \\ &= \frac {-u'}{u} \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' &=0\\ f_1 f_2 &=0\\ f_2^2 f_0 &=-\tan \left (\lambda x \right )^{2} a^{2}+\tan \left (\lambda x \right )^{2} a \lambda -b^{2} \cot \left (\lambda x \right )^{2}+b \cot \left (\lambda x \right )^{2} \lambda +2 a b +a \lambda +b \lambda \end{align*}
Substituting the above terms back in equation (2) gives
\[
u^{\prime \prime }\left (x \right )+\left (-\tan \left (\lambda x \right )^{2} a^{2}+\tan \left (\lambda x \right )^{2} a \lambda -b^{2} \cot \left (\lambda x \right )^{2}+b \cot \left (\lambda x \right )^{2} \lambda +2 a b +a \lambda +b \lambda \right ) u \left (x \right ) = 0
\]
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 \cos \left (\lambda x \right )^{\frac {a}{\lambda }} \sin \left (\lambda x \right )^{\frac {b}{\lambda }}+c_2 \cos \left (\lambda x \right )^{\frac {\lambda -a}{\lambda }} \sin \left (\lambda x \right )^{\frac {\lambda -b}{\lambda }} \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )
\end{equation}
Taking derivative gives \begin{equation}
\tag{4} u^{\prime }\left (x \right ) = -\frac {c_1 \cos \left (\lambda x \right )^{\frac {a}{\lambda }} a \sin \left (\lambda x \right ) \sin \left (\lambda x \right )^{\frac {b}{\lambda }}}{\cos \left (\lambda x \right )}+\frac {c_1 \cos \left (\lambda x \right )^{\frac {a}{\lambda }} \sin \left (\lambda x \right )^{\frac {b}{\lambda }} b \cos \left (\lambda x \right )}{\sin \left (\lambda x \right )}-\frac {c_2 \cos \left (\lambda x \right )^{\frac {\lambda -a}{\lambda }} \left (\lambda -a \right ) \sin \left (\lambda x \right ) \sin \left (\lambda x \right )^{\frac {\lambda -b}{\lambda }} \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )}{\cos \left (\lambda x \right )}+\frac {c_2 \cos \left (\lambda x \right )^{\frac {\lambda -a}{\lambda }} \sin \left (\lambda x \right )^{\frac {\lambda -b}{\lambda }} \left (\lambda -b \right ) \cos \left (\lambda x \right ) \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )}{\sin \left (\lambda x \right )}+\frac {4 c_2 \cos \left (\lambda x \right )^{\frac {\lambda -a}{\lambda }} \sin \left (\lambda x \right )^{\frac {\lambda -b}{\lambda }} \left (-b +\lambda -a \right ) \operatorname {hypergeom}\left (\left [2, \frac {-b +\lambda -a}{\lambda }+1\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }+1\right ], \cos \left (\lambda x \right )^{2}\right ) \cos \left (\lambda x \right ) \lambda \sin \left (\lambda x \right )}{-3 \lambda +2 a}
\end{equation}
Substituting equations (3,4) into (1) results in \begin{align*}
y &= \frac {-u'}{f_2 u} \\
y &= \frac {-u'}{u} \\
y &= -\frac {-\frac {c_1 \cos \left (\lambda x \right )^{\frac {a}{\lambda }} a \sin \left (\lambda x \right ) \sin \left (\lambda x \right )^{\frac {b}{\lambda }}}{\cos \left (\lambda x \right )}+\frac {c_1 \cos \left (\lambda x \right )^{\frac {a}{\lambda }} \sin \left (\lambda x \right )^{\frac {b}{\lambda }} b \cos \left (\lambda x \right )}{\sin \left (\lambda x \right )}-\frac {c_2 \cos \left (\lambda x \right )^{\frac {\lambda -a}{\lambda }} \left (\lambda -a \right ) \sin \left (\lambda x \right ) \sin \left (\lambda x \right )^{\frac {\lambda -b}{\lambda }} \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )}{\cos \left (\lambda x \right )}+\frac {c_2 \cos \left (\lambda x \right )^{\frac {\lambda -a}{\lambda }} \sin \left (\lambda x \right )^{\frac {\lambda -b}{\lambda }} \left (\lambda -b \right ) \cos \left (\lambda x \right ) \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )}{\sin \left (\lambda x \right )}+\frac {4 c_2 \cos \left (\lambda x \right )^{\frac {\lambda -a}{\lambda }} \sin \left (\lambda x \right )^{\frac {\lambda -b}{\lambda }} \left (-b +\lambda -a \right ) \operatorname {hypergeom}\left (\left [2, \frac {-b +\lambda -a}{\lambda }+1\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }+1\right ], \cos \left (\lambda x \right )^{2}\right ) \cos \left (\lambda x \right ) \lambda \sin \left (\lambda x \right )}{-3 \lambda +2 a}}{c_1 \cos \left (\lambda x \right )^{\frac {a}{\lambda }} \sin \left (\lambda x \right )^{\frac {b}{\lambda }}+c_2 \cos \left (\lambda x \right )^{\frac {\lambda -a}{\lambda }} \sin \left (\lambda x \right )^{\frac {\lambda -b}{\lambda }} \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )} \\
\end{align*}
Doing change of constants, the above solution becomes \[
y = -\frac {-\frac {\cos \left (\lambda x \right )^{\frac {a}{\lambda }} a \sin \left (\lambda x \right ) \sin \left (\lambda x \right )^{\frac {b}{\lambda }}}{\cos \left (\lambda x \right )}+\frac {\cos \left (\lambda x \right )^{\frac {a}{\lambda }} \sin \left (\lambda x \right )^{\frac {b}{\lambda }} b \cos \left (\lambda x \right )}{\sin \left (\lambda x \right )}-\frac {c_3 \cos \left (\lambda x \right )^{\frac {\lambda -a}{\lambda }} \left (\lambda -a \right ) \sin \left (\lambda x \right ) \sin \left (\lambda x \right )^{\frac {\lambda -b}{\lambda }} \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )}{\cos \left (\lambda x \right )}+\frac {c_3 \cos \left (\lambda x \right )^{\frac {\lambda -a}{\lambda }} \sin \left (\lambda x \right )^{\frac {\lambda -b}{\lambda }} \left (\lambda -b \right ) \cos \left (\lambda x \right ) \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )}{\sin \left (\lambda x \right )}+\frac {4 c_3 \cos \left (\lambda x \right )^{\frac {\lambda -a}{\lambda }} \sin \left (\lambda x \right )^{\frac {\lambda -b}{\lambda }} \left (-b +\lambda -a \right ) \operatorname {hypergeom}\left (\left [2, \frac {-b +\lambda -a}{\lambda }+1\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }+1\right ], \cos \left (\lambda x \right )^{2}\right ) \cos \left (\lambda x \right ) \lambda \sin \left (\lambda x \right )}{-3 \lambda +2 a}}{\cos \left (\lambda x \right )^{\frac {a}{\lambda }} \sin \left (\lambda x \right )^{\frac {b}{\lambda }}+c_3 \cos \left (\lambda x \right )^{\frac {\lambda -a}{\lambda }} \sin \left (\lambda x \right )^{\frac {\lambda -b}{\lambda }} \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )}
\]
Simplifying the above gives
\begin{align*}
y &= \frac {4 c_3 \lambda \cos \left (\lambda x \right )^{2} \sin \left (\lambda x \right )^{2} \left (a -\lambda +b \right ) \operatorname {hypergeom}\left (\left [2, \frac {2 \lambda -a -b}{\lambda }\right ], \left [-\frac {-5 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )-2 \left (\left (-3 \lambda ^{2}+\frac {\left (7 a +3 b \right ) \lambda }{2}-a b \right ) \cos \left (\lambda x \right )^{2}+a^{2} \sin \left (\lambda x \right )^{2}-\frac {5 \lambda \left (a -\frac {3 \lambda }{5}\right )}{2}\right ) c_3 \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )+2 \left (-\frac {3 \lambda }{2}+a \right ) \sin \left (\lambda x \right )^{\frac {2 b}{\lambda }} \left (a \tan \left (\lambda x \right )-\cot \left (\lambda x \right ) b \right ) \cos \left (\lambda x \right )^{\frac {2 a}{\lambda }}}{\left (-3 \lambda +2 a \right ) \left (\cos \left (\lambda x \right )^{\frac {2 a}{\lambda }} \sin \left (\lambda x \right )^{\frac {2 b}{\lambda }}+c_3 \cos \left (\lambda x \right ) \sin \left (\lambda x \right ) \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )\right )} \\
\end{align*}
Summary of solutions found
\begin{align*}
y &= \frac {4 c_3 \lambda \cos \left (\lambda x \right )^{2} \sin \left (\lambda x \right )^{2} \left (a -\lambda +b \right ) \operatorname {hypergeom}\left (\left [2, \frac {2 \lambda -a -b}{\lambda }\right ], \left [-\frac {-5 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )-2 \left (\left (-3 \lambda ^{2}+\frac {\left (7 a +3 b \right ) \lambda }{2}-a b \right ) \cos \left (\lambda x \right )^{2}+a^{2} \sin \left (\lambda x \right )^{2}-\frac {5 \lambda \left (a -\frac {3 \lambda }{5}\right )}{2}\right ) c_3 \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )+2 \left (-\frac {3 \lambda }{2}+a \right ) \sin \left (\lambda x \right )^{\frac {2 b}{\lambda }} \left (a \tan \left (\lambda x \right )-\cot \left (\lambda x \right ) b \right ) \cos \left (\lambda x \right )^{\frac {2 a}{\lambda }}}{\left (-3 \lambda +2 a \right ) \left (\cos \left (\lambda x \right )^{\frac {2 a}{\lambda }} \sin \left (\lambda x \right )^{\frac {2 b}{\lambda }}+c_3 \cos \left (\lambda x \right ) \sin \left (\lambda x \right ) \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )\right )} \\
\end{align*}
2.13.8.2 ✓ Maple. Time used: 0.004 (sec). Leaf size: 268
ode:=diff(y(x),x) = y(x)^2+lambda*a+b*lambda+2*a*b+a*(lambda-a)*tan(lambda*x)^2+b*(lambda-b)*cot(lambda*x)^2;
dsolve(ode,y(x), singsol=all);
\[
y = \frac {4 c_1 \lambda \cos \left (\lambda x \right )^{2} \sin \left (\lambda x \right )^{2} \left (a +b -\lambda \right ) \operatorname {hypergeom}\left (\left [2, \frac {2 \lambda -a -b}{\lambda }\right ], \left [-\frac {-5 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )-2 \left (\left (-3 \lambda ^{2}+\left (\frac {7 a}{2}+\frac {3 b}{2}\right ) \lambda -a b \right ) \cos \left (\lambda x \right )^{2}+a^{2} \sin \left (\lambda x \right )^{2}-\frac {5 \lambda \left (a -\frac {3 \lambda }{5}\right )}{2}\right ) c_1 \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )+2 \left (\tan \left (\lambda x \right ) a -b \cot \left (\lambda x \right )\right ) \left (a -\frac {3 \lambda }{2}\right ) \sin \left (\lambda x \right )^{\frac {2 b}{\lambda }} \cos \left (\lambda x \right )^{\frac {2 a}{\lambda }}}{\left (-3 \lambda +2 a \right ) \left (c_1 \cos \left (\lambda x \right ) \sin \left (\lambda x \right ) \operatorname {hypergeom}\left (\left [1, \frac {-b +\lambda -a}{\lambda }\right ], \left [-\frac {-3 \lambda +2 a}{2 \lambda }\right ], \cos \left (\lambda x \right )^{2}\right )+\cos \left (\lambda x \right )^{\frac {2 a}{\lambda }} \sin \left (\lambda x \right )^{\frac {2 b}{\lambda }}\right )}
\]
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 Special
trying Riccati sub-methods:
trying Riccati_symmetries
trying Riccati to 2nd Order
-> Calling odsolve with the ODE, diff(diff(y(x),x),x) = (a^2*tan(lambda*x)^2
-a*tan(lambda*x)^2*lambda+b^2*cot(lambda*x)^2-b*cot(lambda*x)^2*lambda-2*a*b-
lambda*a-lambda*b)*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
-> Heun: Equivalence to the GHE or one of its 4 confluent cases under a \
power @ Moebius
-> trying a solution of the form r0(x) * Y + r1(x) * Y where Y = exp(int\
(r(x), dx)) * 2F1([a1, a2], [b1], f)
-> Trying changes of variables to rationalize or make the ODE simpler
trying a quadrature
checking if the LODE has constant coefficients
checking if the LODE is of Euler type
trying a symmetry of the form [xi=0, eta=F(x)]
checking if the LODE is missing y
-> Trying a Liouvillian solution using Kovacics algorithm
A Liouvillian solution exists
Reducible group (found an exponential solution)
Group is reducible, not completely reducible
Solution has integrals. Trying a special function solution free of \
integrals...
-> Trying a solution in terms of special functions:
-> Bessel
-> elliptic
-> Legendre
-> Whittaker
-> hyper3: Equivalence to 1F1 under a power @ Moebius
-> hypergeometric
-> heuristic approach
<- heuristic approach successful
<- hypergeometric successful
<- special function solution successful
-> Trying to convert hypergeometric functions to elementary form\
...
<- elementary form for at least one hypergeometric solution is a\
chieved - returning with no uncomputed integrals
<- Kovacics algorithm successful
Change of variables used:
[x = 1/lambda*arccos(t)]
Linear ODE actually solved:
(a^2*t^4+2*a*b*t^4+b^2*t^4-2*a^2*t^2-2*a*b*t^2+a*lambda*t^2-b*lambd\
a*t^2+a^2-a*lambda)*u(t)+(-lambda^2*t^5+lambda^2*t^3)*diff(u(t),t)+(-lambda^2*t\
^6+2*lambda^2*t^4-lambda^2*t^2)*diff(diff(u(t),t),t) = 0
<- change of variables successful
<- Riccati to 2nd Order successful
Maple step by step
\[ \begin {array}{lll} & {} & \textrm {Let's solve}\hspace {3pt} \\ {} & {} & \frac {d}{d x}y \left (x \right )=y \left (x \right )^{2}+\lambda a +\lambda b +2 a b +a \left (\lambda -a \right ) \tan \left (\lambda x \right )^{2}+b \left (\lambda -b \right ) \cot \left (\lambda x \right )^{2} \\ \bullet & {} & \textrm {Highest derivative means the order of the ODE is}\hspace {3pt} 1 \\ {} & {} & \frac {d}{d x}y \left (x \right ) \\ \bullet & {} & \textrm {Solve for the highest derivative}\hspace {3pt} \\ {} & {} & \frac {d}{d x}y \left (x \right )=y \left (x \right )^{2}+\lambda a +\lambda b +2 a b +a \left (\lambda -a \right ) \tan \left (\lambda x \right )^{2}+b \left (\lambda -b \right ) \cot \left (\lambda x \right )^{2} \end {array} \]
2.13.8.3 ✗ Mathematica
ode=D[y[x],x]==y[x]^2+\[Lambda]*a+\[Lambda]*b+2*a*b+a*(\[Lambda]-a)*Tan[\[Lambda]*x]^2+b*(\[Lambda]-b)*Cot[\[Lambda]*x]^2;
ic={};
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
Not solved
2.13.8.4 ✗ Sympy
from sympy import *
x = symbols("x")
a = symbols("a")
b = symbols("b")
lambda_ = symbols("lambda_")
y = Function("y")
ode = Eq(-2*a*b - a*lambda_ - a*(-a + lambda_)*tan(lambda_*x)**2 - b*lambda_ - b*(-b + lambda_)/tan(lambda_*x)**2 - y(x)**2 + Derivative(y(x), x),0)
ics = {}
dsolve(ode,func=y(x),ics=ics)
NotImplementedError : The given ODE a**2*tan(lambda_*x)**2 - 2*a*b - a*lambda_*tan(lambda_*x)**2 - a
Python version: 3.12.3 (main, Aug 14 2025, 17:47:21) [GCC 13.3.0]
Sympy version 1.14.0
classify_ode(ode,func=y(x))
('factorable', 'lie_group')