82.44.2 problem Ex. 2

Internal problem ID [18966]
Book : Introductory Course On Differential Equations by Daniel A Murray. Longmans Green and Co. NY. 1924
Section : Chapter VIII. Exact differential equations, and equations of particular forms. Integration in series. problems at page 99
Problem number : Ex. 2
Date solved : Tuesday, January 28, 2025 at 12:40:58 PM
CAS classification : [[_2nd_order, _missing_x], [_2nd_order, _exact, _nonlinear], [_2nd_order, _reducible, _mu_x_y1], [_2nd_order, _reducible, _mu_xy]]

\begin{align*} y y^{\prime \prime }+{y^{\prime }}^{2}&=1 \end{align*}

Solution by Maple

Time used: 0.017 (sec). Leaf size: 35

dsolve(y(x)*diff(y(x),x$2)+diff(y(x),x)^2=1,y(x), singsol=all)
 
\begin{align*} y \left (x \right ) &= \sqrt {-2 c_{1} x +x^{2}+2 c_{2}} \\ y \left (x \right ) &= -\sqrt {-2 c_{1} x +x^{2}+2 c_{2}} \\ \end{align*}

Solution by Mathematica

Time used: 0.578 (sec). Leaf size: 79

DSolve[y[x]*D[y[x],{x,2}]+D[y[x],x]^2==1,y[x],x,IncludeSingularSolutions -> True]
 
\begin{align*} y(x)\to -\sqrt {(x+c_2){}^2-e^{2 c_1}} \\ y(x)\to \sqrt {(x+c_2){}^2-e^{2 c_1}} \\ y(x)\to -\sqrt {(x+c_2){}^2} \\ y(x)\to \sqrt {(x+c_2){}^2} \\ \end{align*}