31.3.7 problem 5.4

Internal problem ID [5737]
Book : Differential Equations, By George Boole F.R.S. 1865
Section : Chapter 4
Problem number : 5.4
Date solved : Monday, January 27, 2025 at 01:12:17 PM
CAS classification : [[_homogeneous, `class A`], _dAlembert]

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

Solution by Maple

Time used: 0.264 (sec). Leaf size: 18

dsolve((x*cos(y(x)/x)+y(x)*sin(y(x)/x))*y(x)+(x*cos(y(x)/x)-y(x)*sin(y(x)/x))*x*diff(y(x),x)=0,y(x), singsol=all)
 
\[ y \left (x \right ) = x \operatorname {RootOf}\left (\textit {\_Z} \cos \left (\textit {\_Z} \right ) x^{2}-c_{1} \right ) \]

Solution by Mathematica

Time used: 0.341 (sec). Leaf size: 31

DSolve[(x*Cos[y[x]/x]+y[x]*Sin[y[x]/x])*y[x]+(x*Cos[y[x]/x]-y[x]*Sin[y[x]/x])*x*D[y[x],x]==0,y[x],x,IncludeSingularSolutions -> True]
 
\[ \text {Solve}\left [-\log \left (\frac {y(x)}{x}\right )-\log \left (\cos \left (\frac {y(x)}{x}\right )\right )=2 \log (x)+c_1,y(x)\right ] \]