33.16 problem 978

Internal problem ID [4211]

Book: Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section: Various 33
Problem number: 978.
ODE order: 1.
ODE degree: 2.

CAS Maple gives this as type [[_homogeneous, `class A`], _rational, _dAlembert]

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

Solution by Maple

Time used: 0.078 (sec). Leaf size: 107

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

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

Solution by Mathematica

Time used: 7.875 (sec). Leaf size: 233

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

\begin{align*} y(x)\to -\sqrt {-x^2-4 \sqrt {2} x \cosh (c_1)-4 \sqrt {2} x \sinh (c_1)-4 \cosh (2 c_1)-4 \sinh (2 c_1)} y(x)\to \sqrt {-x^2-4 \sqrt {2} x \cosh (c_1)-4 \sqrt {2} x \sinh (c_1)-4 \cosh (2 c_1)-4 \sinh (2 c_1)} y(x)\to -\sqrt {-x^2+4 \sqrt {2} x \cosh (c_1)+4 \sqrt {2} x \sinh (c_1)-4 \cosh (2 c_1)-4 \sinh (2 c_1)} y(x)\to \sqrt {-x^2+4 \sqrt {2} x \cosh (c_1)+4 \sqrt {2} x \sinh (c_1)-4 \cosh (2 c_1)-4 \sinh (2 c_1)} y(x)\to -\sqrt {-x^2} y(x)\to \sqrt {-x^2} \end{align*}