29.23.22 problem 653

Internal problem ID [5244]
Book : Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section : Various 23
Problem number : 653
Date solved : Sunday, March 30, 2025 at 07:30:47 AM
CAS classification : [[_homogeneous, `class G`], _exact, _rational, _Bernoulli]

\begin{align*} 3 x y^{2} y^{\prime }&=2 x -y^{3} \end{align*}

Maple. Time used: 0.004 (sec). Leaf size: 71
ode:=3*x*y(x)^2*diff(y(x),x) = 2*x-y(x)^3; 
dsolve(ode,y(x), singsol=all);
 
\begin{align*} y &= \frac {{\left (\left (x^{2}+c_1 \right ) x^{2}\right )}^{{1}/{3}}}{x} \\ y &= -\frac {{\left (\left (x^{2}+c_1 \right ) x^{2}\right )}^{{1}/{3}} \left (1+i \sqrt {3}\right )}{2 x} \\ y &= \frac {{\left (\left (x^{2}+c_1 \right ) x^{2}\right )}^{{1}/{3}} \left (i \sqrt {3}-1\right )}{2 x} \\ \end{align*}
Mathematica. Time used: 0.216 (sec). Leaf size: 72
ode=3 x y[x]^2 D[y[x],x]==2 x-y[x]^3; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 
\begin{align*} y(x)\to \frac {\sqrt [3]{x^2+c_1}}{\sqrt [3]{x}} \\ y(x)\to -\frac {\sqrt [3]{-1} \sqrt [3]{x^2+c_1}}{\sqrt [3]{x}} \\ y(x)\to \frac {(-1)^{2/3} \sqrt [3]{x^2+c_1}}{\sqrt [3]{x}} \\ \end{align*}
Sympy. Time used: 1.186 (sec). Leaf size: 53
from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(3*x*y(x)**2*Derivative(y(x), x) - 2*x + y(x)**3,0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 
\[ \left [ y{\left (x \right )} = \sqrt [3]{\frac {C_{1}}{x} + x}, \ y{\left (x \right )} = \frac {\left (-1 - \sqrt {3} i\right ) \sqrt [3]{\frac {C_{1}}{x} + x}}{2}, \ y{\left (x \right )} = \frac {\left (-1 + \sqrt {3} i\right ) \sqrt [3]{\frac {C_{1}}{x} + x}}{2}\right ] \]