63.1.52 problem 71

Internal problem ID [15492]
Book : DIFFERENTIAL and INTEGRAL CALCULUS. VOL I. by N. PISKUNOV. MIR PUBLISHERS, Moscow 1969.
Section : Chapter 8. Differential equations. Exercises page 595
Problem number : 71
Date solved : Thursday, October 02, 2025 at 10:18:40 AM
CAS classification : [_Bernoulli]

\begin{align*} y-\cos \left (x \right ) y^{\prime }&=y^{2} \cos \left (x \right ) \left (1-\sin \left (x \right )\right ) \end{align*}
Maple. Time used: 0.003 (sec). Leaf size: 27
ode:=y(x)-diff(y(x),x)*cos(x) = y(x)^2*cos(x)*(1-sin(x)); 
dsolve(ode,y(x), singsol=all);
 
\[ y = \frac {\cos \left (x \right )+\sin \left (x \right )+1}{\left (\sin \left (x \right )+c_1 \right ) \left (-\sin \left (x \right )+\cos \left (x \right )+1\right )} \]
Mathematica. Time used: 0.264 (sec). Leaf size: 41
ode=y[x]-D[y[x],x]*Cos[x]==y[x]^2*Cos[x]*(1-Sin[x]); 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 
\begin{align*} y(x)&\to \frac {e^{2 \text {arctanh}\left (\tan \left (\frac {x}{2}\right )\right )}}{\cos (x) e^{2 \text {arctanh}\left (\tan \left (\frac {x}{2}\right )\right )}+c_1}\\ y(x)&\to 0 \end{align*}
Sympy. Time used: 1.385 (sec). Leaf size: 39
from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq((sin(x) - 1)*y(x)**2*cos(x) + y(x) - cos(x)*Derivative(y(x), x),0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 
\[ y{\left (x \right )} = \frac {\sqrt {\sin {\left (x \right )} + 1}}{\left (C_{1} - \int \sqrt {\sin {\left (x \right )} - 1} \sqrt {\sin {\left (x \right )} + 1}\, dx\right ) \sqrt {\sin {\left (x \right )} - 1}} \]