9.22 problem 1877

Internal problem ID [9456]

Book: Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section: Chapter 8, system of first order odes
Problem number: 1877.
ODE order: 1.
ODE degree: 1.

Solve \begin {align*} x^{\prime }\relax (t )&=-\frac {y \relax (t )}{t}\\ y^{\prime }\relax (t )&=-\frac {x \relax (t )}{t} \end {align*}

Solution by Maple

Time used: 0.067 (sec). Leaf size: 31

dsolve({t*diff(x(t),t)+y(t)=0,t*diff(y(t),t)+x(t)=0},{x(t), y(t)}, singsol=all)
 

\[ x \relax (t ) = \frac {c_{2} t^{2}+c_{1}}{t} \] \[ y \relax (t ) = \frac {-c_{2} t^{2}+c_{1}}{t} \]

Solution by Mathematica

Time used: 0.002 (sec). Leaf size: 31

DSolve[{t*x'[t]+y[t]==0,t*y'[t]+x[t]==0},{x[t],y[t]},t,IncludeSingularSolutions -> True]
 

\begin{align*} x(t)\to c_1 t+\frac {c_2}{t} \\ y(t)\to \frac {c_2}{t}-c_1 t \\ \end{align*}