32.6.7 problem Exercise 12.7, page 103

Internal problem ID [5872]
Book : Ordinary Differential Equations, By Tenenbaum and Pollard. Dover, NY 1963
Section : Chapter 2. Special types of differential equations of the first kind. Lesson 12, Miscellaneous Methods
Problem number : Exercise 12.7, page 103
Date solved : Monday, January 27, 2025 at 01:22:35 PM
CAS classification : [[_homogeneous, `class A`], _rational, _dAlembert]

\begin{align*} -y+x y^{\prime }&=\sqrt {x^{2}+y^{2}} \end{align*}

Solution by Maple

Time used: 0.006 (sec). Leaf size: 26

dsolve(x*diff(y(x),x)-y(x)=sqrt(x^2+y(x)^2),y(x), singsol=all)
 
\[ \frac {-c_{1} x^{2}+y \left (x \right )+\sqrt {x^{2}+y \left (x \right )^{2}}}{x^{2}} = 0 \]

Solution by Mathematica

Time used: 0.312 (sec). Leaf size: 13

DSolve[x*D[y[x],x]-y[x]==Sqrt[x^2+y[x]^2],y[x],x,IncludeSingularSolutions -> True]
 
\[ y(x)\to x \sinh (\log (x)+c_1) \]