29.18.1 problem 477

Internal problem ID [5075]
Book : Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section : Various 18
Problem number : 477
Date solved : Sunday, March 30, 2025 at 06:35:31 AM
CAS classification : [_separable]

\begin{align*} 3 \left (2-y\right ) y^{\prime }+x y&=0 \end{align*}

Maple. Time used: 0.012 (sec). Leaf size: 19
ode:=3*(2-y(x))*diff(y(x),x)+x*y(x) = 0; 
dsolve(ode,y(x), singsol=all);
 
\[ y = -2 \operatorname {LambertW}\left (-\frac {{\mathrm e}^{-\frac {x^{2}}{12}-\frac {c_1}{6}}}{2}\right ) \]
Mathematica. Time used: 19.238 (sec). Leaf size: 64
ode=3(2-y[x])D[y[x],x]+x y[x]==0; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 
\begin{align*} y(x)\to -2 W\left (-\frac {1}{2} \sqrt {e^{-\frac {x^2}{6}-c_1}}\right ) \\ y(x)\to -2 W\left (\frac {1}{2} \sqrt {e^{-\frac {x^2}{6}-c_1}}\right ) \\ y(x)\to 0 \\ \end{align*}
Sympy. Time used: 37.425 (sec). Leaf size: 296
from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(x*y(x) + (6 - 3*y(x))*Derivative(y(x), x),0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 
\[ \left [ y{\left (x \right )} = - 2 W\left (- \frac {i \sqrt [12]{C_{1} e^{- x^{2}}}}{2}\right ), \ y{\left (x \right )} = - 2 W\left (\frac {i \sqrt [12]{C_{1} e^{- x^{2}}}}{2}\right ), \ y{\left (x \right )} = - 2 W\left (\frac {\sqrt [12]{C_{1} e^{- x^{2}}} \left (-1 + \sqrt {3} i\right )}{4}\right ), \ y{\left (x \right )} = - 2 W\left (\frac {\sqrt [12]{C_{1} e^{- x^{2}}} \left (1 - \sqrt {3} i\right )}{4}\right ), \ y{\left (x \right )} = - 2 W\left (\frac {\sqrt [12]{C_{1} e^{- x^{2}}} \left (-1 - \sqrt {3} i\right )}{4}\right ), \ y{\left (x \right )} = - 2 W\left (\frac {\sqrt [12]{C_{1} e^{- x^{2}}} \left (1 + \sqrt {3} i\right )}{4}\right ), \ y{\left (x \right )} = - 2 W\left (\frac {\sqrt [12]{C_{1} e^{- x^{2}}} \left (- \sqrt {3} + i\right )}{4}\right ), \ y{\left (x \right )} = - 2 W\left (\frac {\sqrt [12]{C_{1} e^{- x^{2}}} \left (\sqrt {3} - i\right )}{4}\right ), \ y{\left (x \right )} = - 2 W\left (\frac {\sqrt [12]{C_{1} e^{- x^{2}}} \left (- \sqrt {3} - i\right )}{4}\right ), \ y{\left (x \right )} = - 2 W\left (\frac {\sqrt [12]{C_{1} e^{- x^{2}}} \left (\sqrt {3} + i\right )}{4}\right ), \ y{\left (x \right )} = - 2 W\left (- \frac {\sqrt [12]{C_{1} e^{- x^{2}}}}{2}\right ), \ y{\left (x \right )} = - 2 W\left (\frac {\sqrt [12]{C_{1} e^{- x^{2}}}}{2}\right )\right ] \]