29.2.1 problem 26

Internal problem ID [4634]
Book : Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section : Various 2
Problem number : 26
Date solved : Sunday, March 30, 2025 at 03:31:43 AM
CAS classification : [_separable]

\begin{align*} y^{\prime }&=y \tan \left (x \right ) \end{align*}

✓ Maple. Time used: 0.001 (sec). Leaf size: 8

ode:=diff(y(x),x) = y(x)*tan(x); 
dsolve(ode,y(x), singsol=all);
 

\[ y = c_1 \sec \left (x \right ) \]

✓ Mathematica. Time used: 0.035 (sec). Leaf size: 15

ode=D[y[x],x]==y[x]*Tan[x]; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 

\begin{align*} y(x)\to c_1 \sec (x) \\ y(x)\to 0 \\ \end{align*}

✓ Sympy. Time used: 0.214 (sec). Leaf size: 7

from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(-y(x)*tan(x) + Derivative(y(x), x),0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 

\[ y{\left (x \right )} = \frac {C_{1}}{\cos {\left (x \right )}} \]