77.1.37 problem 54 (page 96)

Internal problem ID [17856]
Book : V.V. Stepanov, A course of differential equations (in Russian), GIFML. Moscow (1958)
Section : All content
Problem number : 54 (page 96)
Date solved : Monday, March 31, 2025 at 04:36:31 PM
CAS classification : [_exact]

\begin{align*} \frac {\sin \left (\frac {x}{y}\right )}{y}-\frac {y \cos \left (\frac {y}{x}\right )}{x^{2}}+1+\left (\frac {\cos \left (\frac {y}{x}\right )}{x}-\frac {x \sin \left (\frac {x}{y}\right )}{y^{2}}+\frac {1}{y^{2}}\right ) y^{\prime }&=0 \end{align*}

✓ Maple. Time used: 0.020 (sec). Leaf size: 30

ode:=1/y(x)*sin(x/y(x))-y(x)/x^2*cos(y(x)/x)+1+(1/x*cos(y(x)/x)-x/y(x)^2*sin(x/y(x))+1/y(x)^2)*diff(y(x),x) = 0; 
dsolve(ode,y(x), singsol=all);
 

\[ y = \frac {x}{\operatorname {RootOf}\left (-\cos \left (\textit {\_Z} \right ) x +x \sin \left (\frac {1}{\textit {\_Z}}\right )+c_1 x +x^{2}-\textit {\_Z} \right )} \]

✓ Mathematica. Time used: 0.723 (sec). Leaf size: 30

ode=(1/y[x]*Sin[x/y[x]]-y[x]/x^2*Cos[y[x]/x]+1 )+( 1/x*Cos[y[x]/x]-x/y[x]^2*Sin[x/y[x]]+1/y[x]^2 ) *D[y[x],x]==0; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 

\[ \text {Solve}\left [\frac {1}{y(x)}-\sin \left (\frac {y(x)}{x}\right )+\cos \left (\frac {x}{y(x)}\right )-x=c_1,y(x)\right ] \]

✗ Sympy

from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq((-x*sin(x/y(x))/y(x)**2 + y(x)**(-2) + cos(y(x)/x)/x)*Derivative(y(x), x) + 1 + sin(x/y(x))/y(x) - y(x)*cos(y(x)/x)/x**2,0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 

Timed Out