17.1 problem Ex 1

Internal problem ID [11235]

Book: An elementary treatise on differential equations by Abraham Cohen. DC heath publishers. 1906
Section: Chapter IV, differential equations of the first order and higher degree than the first. Article 28. Summary. Page 59
Problem number: Ex 1.
ODE order: 1.
ODE degree: 2.

CAS Maple gives this as type [_quadrature]

\[ \boxed {y^{2} \left ({y^{\prime }}^{2}+1\right )=a^{2}} \]

Solution by Maple

Time used: 0.0 (sec). Leaf size: 59

dsolve(y(x)^2*(1+diff(y(x),x)^2)=a^2,y(x), singsol=all)
 

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

Solution by Mathematica

Time used: 0.344 (sec). Leaf size: 101

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

\begin{align*} y(x)\to -\sqrt {a^2-(x+c_1){}^2} y(x)\to \sqrt {a^2-(x+c_1){}^2} y(x)\to -\sqrt {a^2-(x-c_1){}^2} y(x)\to \sqrt {a^2-(x-c_1){}^2} y(x)\to -a y(x)\to a \end{align*}