Internal problem ID [11571]
Book: A First Course in Differential Equations by J. David Logan. Third Edition. Springer-Verlag,
NY. 2015.
Section: Chapter 4, Linear Systems. Exercises page 237
Problem number: 4(g).
ODE order: 1.
ODE degree: 1.
Solve \begin {align*} x^{\prime }&=5 x-4 y \left (t \right )\\ y^{\prime }\left (t \right )&=x+y \left (t \right ) \end {align*}
✓ Solution by Maple
Time used: 0.063 (sec). Leaf size: 32
dsolve([diff(x(t),t)=5*x(t)-4*y(t),diff(y(t),t)=x(t)+y(t)],[x(t), y(t)], singsol=all)
\[ x \left (t \right ) = {\mathrm e}^{3 t} \left (2 t c_{2} +2 c_{1} +c_{2} \right ) \] \[ y \left (t \right ) = {\mathrm e}^{3 t} \left (t c_{2} +c_{1} \right ) \]
✓ Solution by Mathematica
Time used: 0.004 (sec). Leaf size: 45
DSolve[{x'[t]==5*x[t]-4*y[t],y'[t]==x[t]+y[t]},{x[t],y[t]},t,IncludeSingularSolutions -> True]
\begin{align*} x(t)\to e^{3 t} (2 c_1 t-4 c_2 t+c_1) y(t)\to e^{3 t} ((c_1-2 c_2) t+c_2) \end{align*}