12.1 problem Ex 1

Internal problem ID [11181]

Book: An elementary treatise on differential equations by Abraham Cohen. DC heath publishers. 1906
Section: Chapter 2, differential equations of the first order and the first degree. Article 19. Summary. Page 29
Problem number: Ex 1.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [_separable]

\[ \boxed {x \sqrt {1-y^{2}}+y \sqrt {-x^{2}+1}\, y^{\prime }=0} \]

Solution by Maple

Time used: 0.0 (sec). Leaf size: 40

dsolve(x*sqrt(1-y(x)^2)+y(x)*sqrt(1-x^2)*diff(y(x),x)=0,y(x), singsol=all)
 

\[ \frac {\left (x -1\right ) \left (x +1\right )}{\sqrt {-x^{2}+1}}+\frac {\left (y \left (x \right )-1\right ) \left (y \left (x \right )+1\right )}{\sqrt {1-y \left (x \right )^{2}}}+c_{1} = 0 \]

Solution by Mathematica

Time used: 3.778 (sec). Leaf size: 77

DSolve[x*Sqrt[1-y[x]^2]+y[x]*Sqrt[1-x^2]*y'[x]==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to -\sqrt {x^2-c_1 \left (2 \sqrt {1-x^2}+c_1\right )} y(x)\to \sqrt {x^2-c_1 \left (2 \sqrt {1-x^2}+c_1\right )} y(x)\to -1 y(x)\to 1 \end{align*}