30.19 problem 878

Internal problem ID [3606]

Book: Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section: Various 30
Problem number: 878.
ODE order: 1.
ODE degree: 2.

CAS Maple gives this as type [[_1st_order, _with_linear_symmetries], _Clairaut]

\[ \boxed {\left (a -x \right ) {y^{\prime }}^{2}+y y^{\prime }-b=0} \]

Solution by Maple

Time used: 0.094 (sec). Leaf size: 50

dsolve((a-x)*diff(y(x),x)^2+y(x)*diff(y(x),x)-b = 0,y(x), singsol=all)
 

\begin{align*} y \left (x \right ) = -2 \sqrt {-a b +x b} \\ y \left (x \right ) = 2 \sqrt {-a b +x b} \\ y \left (x \right ) = c_{1} x +\frac {-c_{1}^{2} a +b}{c_{1}} \\ \end{align*}

Solution by Mathematica

Time used: 0.015 (sec). Leaf size: 59

DSolve[(a-x) (y'[x])^2+y[x] y'[x]-b==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to c_1 (x-a)+\frac {b}{c_1} \\ y(x)\to \text {Indeterminate} \\ y(x)\to -2 \sqrt {b (x-a)} \\ y(x)\to 2 \sqrt {b (x-a)} \\ \end{align*}