58.4.16 problem 16

Internal problem ID [14586]
Book : Differential Equations by Shepley L. Ross. Third edition. John Willey. New Delhi. 2004.
Section : Chapter 2, section 2.2 (Separable equations). Exercises page 47
Problem number : 16
Date solved : Thursday, October 02, 2025 at 09:43:11 AM
CAS classification : [_separable]

\begin{align*} 8 \cos \left (y\right )^{2}+\csc \left (x \right )^{2} y^{\prime }&=0 \end{align*}

With initial conditions

\begin{align*} y \left (\frac {\pi }{12}\right )&=\frac {\pi }{4} \\ \end{align*}
Maple. Time used: 0.228 (sec). Leaf size: 20
ode:=8*cos(y(x))^2+csc(x)^2*diff(y(x),x) = 0; 
ic:=[y(1/12*Pi) = 1/4*Pi]; 
dsolve([ode,op(ic)],y(x), singsol=all);
 
\[ y = -\arctan \left (-\frac {\pi }{3}+4 x -2 \sin \left (2 x \right )\right ) \]
Mathematica. Time used: 0.484 (sec). Leaf size: 21
ode=(8*Cos[y[x]]^2)+Csc[x]^2*D[y[x],x]==0; 
ic={y[Pi/12]==Pi/4}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 
\begin{align*} y(x)&\to \arctan \left (-4 x+2 \sin (2 x)+\frac {\pi }{3}\right ) \end{align*}
Sympy
from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(8*cos(y(x))**2 + Derivative(y(x), x)/sin(x)**2,0) 
ics = {y(pi/12): pi/4} 
dsolve(ode,func=y(x),ics=ics)
 
Timed Out