29.33 problem 855

Internal problem ID [4094]

Book: Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section: Various 29
Problem number: 855.
ODE order: 1.
ODE degree: 2.

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

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

Solution by Maple

Time used: 0.047 (sec). Leaf size: 50

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

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

Solution by Mathematica

Time used: 0.924 (sec). Leaf size: 167

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

\begin{align*} \text {Solve}\left [\frac {4 a \arctan \left (\frac {y(x)}{x \sqrt {4 a-\frac {y(x)^2}{x^2}}}\right )+\frac {y(x) \left (\sqrt {4 a-\frac {y(x)^2}{x^2}}-\frac {i y(x)}{x}\right )}{x}}{8 a}=\frac {1}{2} i \log (x)+c_1,y(x)\right ] \text {Solve}\left [\frac {4 a \arctan \left (\frac {y(x)}{x \sqrt {4 a-\frac {y(x)^2}{x^2}}}\right )+\frac {y(x) \left (\sqrt {4 a-\frac {y(x)^2}{x^2}}+\frac {i y(x)}{x}\right )}{x}}{8 a}=c_1-\frac {1}{2} i \log (x),y(x)\right ] \end{align*}