14.16 problem 342

Internal problem ID [15200]

Book: A book of problems in ordinary differential equations. M.L. KRASNOV, A.L. KISELYOV, G.I. MARKARENKO. MIR, MOSCOW. 1983
Section: Chapter 2 (Higher order ODE’s). Section 14. Differential equations admitting of depression of their order. Exercises page 107
Problem number: 342.
ODE order: 2.
ODE degree: 1.

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

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

Solution by Maple

Time used: 0.0 (sec). Leaf size: 15

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

\[ y = -\ln \left (-c_{1} x -c_{2} \right ) \]

Solution by Mathematica

Time used: 1.667 (sec). Leaf size: 16

DSolve[y''[x]==1+y'[x]^2,y[x],x,IncludeSingularSolutions -> True]
 

\[ y(x)\to c_2-\log (\cos (x+c_1)) \]