2.8 problem 31

Internal problem ID [5243]

Book: Schaums Outline. Theory and problems of Differential Equations, 1st edition. Frank Ayres. McGraw Hill 1952
Section: Chapter 4. Equations of first order and first degree (Variable separable). Supplemetary problems. Page 22
Problem number: 31.
ODE order: 1.
ODE degree: 1.

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

\[ \boxed {\sqrt {x^{2}+y^{2}}\, y-x \left (x +\sqrt {x^{2}+y^{2}}\right ) y^{\prime }=0} \]

Solution by Maple

Time used: 0.047 (sec). Leaf size: 60

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

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

Solution by Mathematica

Time used: 0.319 (sec). Leaf size: 43

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

\[ \text {Solve}\left [\sqrt {\frac {y(x)^2}{x^2}+1}+\log \left (\sqrt {\frac {y(x)^2}{x^2}+1}-1\right )=-\log (x)+c_1,y(x)\right ] \]