1.50 problem 50

Internal problem ID [6682]

Book: Second order enumerated odes
Section: section 1
Problem number: 50.
ODE order: 2.
ODE degree: 1.

CAS Maple gives this as type [[_2nd_order, _missing_x], [_2nd_order, _reducible, _mu_x_y1], [_2nd_order, _reducible, _mu_y_y1]]

\[ \boxed {y y^{\prime \prime }+{y^{\prime }}^{3}=0} \]

Solution by Maple

Time used: 0.078 (sec). Leaf size: 27

dsolve(y(x)*diff(y(x),x$2)+diff(y(x),x)^3=0,y(x), singsol=all)
 

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

Solution by Mathematica

Time used: 0.09 (sec). Leaf size: 25

DSolve[y[x]*y''[x]+y'[x]^3==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to e^{W\left (e^{-1-c_1} (x+c_2)\right )+1+c_1} \\ \end{align*}