19.5 problem 5

Internal problem ID [2318]

Book: Differential Equations by Alfred L. Nelson, Karl W. Folley, Max Coral. 3rd ed. DC heath. Boston. 1964
Section: Exercise 37, page 171
Problem number: 5.
ODE order: 1.
ODE degree: 2.

CAS Maple gives this as type [_quadrature]

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

Solution by Maple

Time used: 0.078 (sec). Leaf size: 46

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

\begin{align*} y \left (x \right ) &= \sin \left (\operatorname {RootOf}\left (\sin \left (\textit {\_Z} \right ) \operatorname {csgn}\left (\cos \left (\textit {\_Z} \right )\right ) \cos \left (\textit {\_Z} \right )+\textit {\_Z} +2 c_{1} -2 x \right )\right ) \\ y \left (x \right ) &= \sin \left (\operatorname {RootOf}\left (-\sin \left (\textit {\_Z} \right ) \operatorname {csgn}\left (\cos \left (\textit {\_Z} \right )\right ) \cos \left (\textit {\_Z} \right )-\textit {\_Z} +2 c_{1} -2 x \right )\right ) \\ \end{align*}

Solution by Mathematica

Time used: 0.089 (sec). Leaf size: 105

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

\begin{align*} y(x)\to \text {InverseFunction}\left [\frac {1}{2} \text {$\#$1} \sqrt {1-\text {$\#$1}^2}-\arctan \left (\frac {\sqrt {1-\text {$\#$1}^2}}{\text {$\#$1}+1}\right )\&\right ][-x+c_1] \\ y(x)\to \text {InverseFunction}\left [\frac {1}{2} \text {$\#$1} \sqrt {1-\text {$\#$1}^2}-\arctan \left (\frac {\sqrt {1-\text {$\#$1}^2}}{\text {$\#$1}+1}\right )\&\right ][x+c_1] \\ \end{align*}