2.26 problem 26

Internal problem ID [5774]

Book: Ordinary differential equations and calculus of variations. Makarets and Reshetnyak. Wold Scientific. Singapore. 1995
Section: Chapter 1. First order differential equations. Section 1.2 Homogeneous equations problems. page 12
Problem number: 26.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [[_homogeneous, `class A`], _rational, _dAlembert]

\[ \boxed {y^{\prime } x -y-\sqrt {x^{2}+y^{2}}=0} \]

Solution by Maple

Time used: 0.016 (sec). Leaf size: 27

dsolve(x*diff(y(x),x)-y(x)=sqrt(x^2+y(x)^2),y(x), singsol=all)
 

\[ \frac {y \left (x \right )}{x^{2}}+\frac {\sqrt {x^{2}+y \left (x \right )^{2}}}{x^{2}}-c_{1} = 0 \]

Solution by Mathematica

Time used: 0.331 (sec). Leaf size: 27

DSolve[x*y'[x]-y[x]==Sqrt[x^2+y[x]^2],y[x],x,IncludeSingularSolutions -> True]
 

\[ y(x)\to \frac {1}{2} e^{-c_1} \left (-1+e^{2 c_1} x^2\right ) \]