18.24 problem 24

Internal problem ID [2296]

Book: Differential Equations by Alfred L. Nelson, Karl W. Folley, Max Coral. 3rd ed. DC heath. Boston. 1964
Section: Exercise 35, page 157
Problem number: 24.
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]]

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

Solution by Maple

Time used: 0.047 (sec). Leaf size: 35

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

\begin{align*} y \left (x \right ) &= 0 \\ y \left (x \right ) &= \sqrt {2 \,{\mathrm e}^{x} c_{1} +2 c_{2}} \\ y \left (x \right ) &= -\sqrt {2 \,{\mathrm e}^{x} c_{1} +2 c_{2}} \\ \end{align*}

Solution by Mathematica

Time used: 1.093 (sec). Leaf size: 41

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

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