Internal problem ID [6775]
Book: Elementary differential equations. By Earl D. Rainville, Phillip E. Bedient. Macmilliam
Publishing Co. NY. 6th edition. 1981.
Section: CHAPTER 16. Nonlinear equations. Section 94. Factoring the left member. EXERCISES
Page 309
Problem number: 9.
ODE order: 1.
ODE degree: 2.
CAS Maple gives this as type [[_homogeneous, `class A`], _rational, [_Abel, `2nd type`, `class A`]]
\[ \boxed {\left (x +y\right )^{2} {y^{\prime }}^{2}-y^{2}=0} \]
✓ Solution by Maple
Time used: 0.031 (sec). Leaf size: 48
dsolve((x+y(x))^2*diff(y(x),x)^2=y(x)^2,y(x), singsol=all)
\begin{align*} y \left (x \right ) = {\mathrm e}^{\operatorname {LambertW}\left (x \,{\mathrm e}^{c_{1}}\right )-c_{1}} y \left (x \right ) = -x -\sqrt {x^{2}+2 c_{1}} y \left (x \right ) = -x +\sqrt {x^{2}+2 c_{1}} \end{align*}
✓ Solution by Mathematica
Time used: 4.023 (sec). Leaf size: 101
DSolve[(x+y[x])^2*(y'[x])^2==y[x]^2,y[x],x,IncludeSingularSolutions -> True]
\begin{align*} y(x)\to -x-\sqrt {x^2+e^{2 c_1}} y(x)\to -x+\sqrt {x^2+e^{2 c_1}} y(x)\to \frac {x}{W\left (e^{-c_1} x\right )} y(x)\to 0 y(x)\to -\sqrt {x^2}-x y(x)\to \sqrt {x^2}-x \end{align*}