4.4 problem 4

Internal problem ID [6071]

Book: Elementary differential equations. By Earl D. Rainville, Phillip E. Bedient. Macmilliam Publishing Co. NY. 6th edition. 1981.
Section: CHAPTER 16. Nonlinear equations. Section 101. Independent variable missing. EXERCISES Page 324
Problem number: 4.
ODE order: 2.
ODE degree: 1.

CAS Maple gives this as type [[_2nd_order, _missing_x], [_2nd_order, _exact, _nonlinear], _Liouville, [_2nd_order, _reducible, _mu_x_y1], [_2nd_order, _reducible, _mu_xy]]

Solve \begin {gather*} \boxed {y y^{\prime \prime }+\left (y^{\prime }\right )^{2}=0} \end {gather*}

Solution by Maple

Time used: 0.172 (sec). Leaf size: 33

dsolve(y(x)*diff(y(x),x$2)+diff(y(x),x)^2=0,y(x), singsol=all)
 

\begin{align*} y \relax (x ) = 0 \\ y \relax (x ) = \sqrt {2 c_{1} x +2 c_{2}} \\ y \relax (x ) = -\sqrt {2 c_{1} x +2 c_{2}} \\ \end{align*}

Solution by Mathematica

Time used: 0.106 (sec). Leaf size: 20

DSolve[y[x]*y''[x]+(y'[x])^2==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to c_2 \sqrt {2 x-c_1} \\ \end{align*}