Internal problem ID [6849]
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: 32.
ODE order: 2.
ODE degree: 1.
CAS Maple gives this as type [[_2nd_order, _missing_x], [_2nd_order, _reducible, _mu_x_y1]]
\[ \boxed {\left (1+y^{2}\right ) y^{\prime \prime }+{y^{\prime }}^{3}+y^{\prime }=0} \]
✓ Solution by Maple
Time used: 0.187 (sec). Leaf size: 118
dsolve((1+y(x)^2)*diff(y(x),x$2)+diff(y(x),x)^3+diff(y(x),x)=0,y(x), singsol=all)
\begin{align*} y \left (x \right ) &= -i \\ y \left (x \right ) &= i \\ y \left (x \right ) &= c_{1} \\ y \left (x \right ) &= \frac {i c_{1} -i-{\mathrm e}^{\frac {-4 \operatorname {LambertW}\left (-\frac {i {\mathrm e}^{\frac {\left (-c_{2} -x +1\right ) c_{1}^{2}+\left (-2 c_{2} -2 x -2\right ) c_{1} -x -c_{2} +1}{4 c_{1}}} \left (c_{1} -1\right )}{4 c_{1}}\right ) c_{1} +\left (-c_{2} -x +1\right ) c_{1}^{2}+\left (-2 c_{2} -2 x -2\right ) c_{1} -x -c_{2} +1}{4 c_{1}}}}{c_{1} +1} \\ \end{align*}
✓ Solution by Mathematica
Time used: 57.998 (sec). Leaf size: 56
DSolve[(1+y[x]^2)*y''[x]+(y'[x])^3+y'[x]==0,y[x],x,IncludeSingularSolutions -> True]
\begin{align*} y(x)\to \csc (c_1) \sec (c_1) W\left (\sin (c_1) e^{-\left ((x+c_2) \cos ^2(c_1)\right )-\sin ^2(c_1)}\right )+\tan (c_1) \\ y(x)\to e^{-x-c_2} \\ \end{align*}