2.303 problem 879

Internal problem ID [8459]

Book: Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section: Chapter 1, Additional non-linear first order
Problem number: 879.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [[_1st_order, _with_symmetry_[F(x),G(x)*y+H(x)]]]

Solve \begin {gather*} \boxed {y^{\prime }+\frac {-y x -y+\sqrt {y^{2}+x^{2}}\, x^{2}-x \sqrt {y^{2}+x^{2}}\, y}{x \left (x +1\right )}=0} \end {gather*}

Solution by Maple

Time used: 0.157 (sec). Leaf size: 55

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

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

Solution by Mathematica

Time used: 4.978 (sec). Leaf size: 69

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

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