1.430 problem 431

Internal problem ID [8767]

Book: Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section: Chapter 1, linear first order
Problem number: 431.
ODE order: 1.
ODE degree: 2.

CAS Maple gives this as type [_separable]

\[ \boxed {x^{2} {y^{\prime }}^{2}-y^{4}+y^{2}=0} \]

Solution by Maple

Time used: 0.078 (sec). Leaf size: 66

dsolve(x^2*diff(y(x),x)^2-y(x)^4+y(x)^2 = 0,y(x), singsol=all)
 

\begin{align*} y \left (x \right ) = -1 y \left (x \right ) = 1 y \left (x \right ) = 0 y \left (x \right ) = \frac {\sqrt {\tan \left (-\ln \left (x \right )+c_{1} \right )^{2}+1}}{\tan \left (-\ln \left (x \right )+c_{1} \right )} y \left (x \right ) = -\frac {\sqrt {\tan \left (-\ln \left (x \right )+c_{1} \right )^{2}+1}}{\tan \left (-\ln \left (x \right )+c_{1} \right )} \end{align*}

Solution by Mathematica

Time used: 1.514 (sec). Leaf size: 88

DSolve[y[x]^2 - y[x]^4 + x^2*y'[x]^2==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to -\sqrt {\sec ^2(-\log (x)+c_1)} y(x)\to \sqrt {\sec ^2(-\log (x)+c_1)} y(x)\to -\sqrt {\sec ^2(\log (x)+c_1)} y(x)\to \sqrt {\sec ^2(\log (x)+c_1)} y(x)\to -1 y(x)\to 0 y(x)\to 1 \end{align*}