54.10.11 problem 1925

Internal problem ID [13145]
Book : Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section : Chapter 9, system of higher order odes
Problem number : 1925
Date solved : Sunday, October 12, 2025 at 02:35:48 AM
CAS classification : system_of_ODEs

\begin{align*} \left (\frac {d}{d t}x \left (t \right )\right )^{2}+t \left (\frac {d}{d t}x \left (t \right )\right )+a \left (\frac {d}{d t}y \left (t \right )\right )-x \left (t \right )&=0\\ \left (\frac {d}{d t}x \left (t \right )\right ) \left (\frac {d}{d t}y \left (t \right )\right )+t \left (\frac {d}{d t}y \left (t \right )\right )-y \left (t \right )&=0 \end{align*}
Maple. Time used: 0.315 (sec). Leaf size: 220
ode:=[diff(x(t),t)^2+t*diff(x(t),t)+a*diff(y(t),t)-x(t) = 0, diff(x(t),t)*diff(y(t),t)+t*diff(y(t),t)-y(t) = 0]; 
dsolve(ode);
 
\begin{align*} \left [\left \{x \left (t \right ) &= -\frac {t^{2}}{3}\right \}, \left \{y \left (t \right ) = -\frac {t^{3}}{27 a}\right \}\right ] \\ \left [\{x \left (t \right ) = c_1 t +c_2\}, \left \{y \left (t \right ) &= \frac {-\left (\frac {d}{d t}x \left (t \right )\right )^{3}-2 \left (\frac {d}{d t}x \left (t \right )\right )^{2} t -\left (\frac {d}{d t}x \left (t \right )\right ) t^{2}+\left (\frac {d}{d t}x \left (t \right )\right ) x \left (t \right )+x \left (t \right ) t}{a}\right \}\right ] \\ \left [\left \{x \left (t \right ) &= -\frac {5 t^{2}}{12}-\frac {t \left (-t -\sqrt {3}\, c_1 \right )}{6}+\frac {c_1^{2}}{4}, x \left (t \right ) = -\frac {5 t^{2}}{12}-\frac {t \left (-t +\sqrt {3}\, c_1 \right )}{6}+\frac {c_1^{2}}{4}, x \left (t \right ) = -\frac {5 t^{2}}{12}+\frac {t \left (t -\sqrt {3}\, c_1 \right )}{6}+\frac {c_1^{2}}{4}, x \left (t \right ) = -\frac {5 t^{2}}{12}+\frac {t \left (t +\sqrt {3}\, c_1 \right )}{6}+\frac {c_1^{2}}{4}\right \}, \left \{y \left (t \right ) = -\frac {-2 \left (\frac {d}{d t}x \left (t \right )\right ) t^{2}-2 t^{3}-6 \left (\frac {d}{d t}x \left (t \right )\right ) x \left (t \right )-7 x \left (t \right ) t}{9 a}\right \}\right ] \\ \end{align*}
Mathematica. Time used: 0.007 (sec). Leaf size: 28
ode={D[x[t],t]^2+t*D[x[t],t]+a*D[y[t],t]-x[t]==0,D[x[t],t]*D[y[t],t]+t*D[y[t],t]-y[t]==0}; 
ic={}; 
DSolve[{ode,ic},{x[t],y[t]},t,IncludeSingularSolutions->True]
 
\begin{align*} x(t)&\to a c_2+c_1 t+c_1{}^2\\ y(t)&\to c_2 (t+c_1) \end{align*}
Sympy. Time used: 1.036 (sec). Leaf size: 20
from sympy import * 
t = symbols("t") 
a = symbols("a") 
x = Function("x") 
y = Function("y") 
ode=[Eq(a*Derivative(y(t), t) + t*Derivative(x(t), t) - x(t) + Derivative(x(t), t)**2,0),Eq(t*Derivative(y(t), t) - y(t) + Derivative(x(t), t)*Derivative(y(t), t),0)] 
ics = {} 
dsolve(ode,func=[x(t),y(t)],ics=ics)
 
\[ \left \{x{\left (t \right )} = C_{1}^{2} + C_{1} t + C_{2} a, y{\left (t \right )} = C_{1} C_{2} + C_{2} t\right \} \]