Internal problem ID [11556]
Book: A First Course in Differential Equations by J. David Logan. Third Edition. Springer-Verlag,
NY. 2015.
Section: Chapter 4, Linear Systems. Exercises page 202
Problem number: 3(b).
ODE order: 1.
ODE degree: 1.
Solve \begin {align*} x^{\prime }&=-3 x+3 y \left (t \right )\\ y^{\prime }\left (t \right )&=x+2 y \left (t \right )-1 \end {align*}
✓ Solution by Maple
Time used: 0.11 (sec). Leaf size: 88
dsolve([diff(x(t),t)=-3*x(t)+3*y(t),diff(y(t),t)=x(t)+2*y(t)-1],[x(t), y(t)], singsol=all)
\[ x \left (t \right ) = -\frac {{\mathrm e}^{-\frac {\left (1+\sqrt {37}\right ) t}{2}} c_{1} \sqrt {37}}{2}+\frac {{\mathrm e}^{\frac {\left (-1+\sqrt {37}\right ) t}{2}} c_{2} \sqrt {37}}{2}-\frac {5 \,{\mathrm e}^{-\frac {\left (1+\sqrt {37}\right ) t}{2}} c_{1}}{2}-\frac {5 \,{\mathrm e}^{\frac {\left (-1+\sqrt {37}\right ) t}{2}} c_{2}}{2}+\frac {1}{3} \] \[ y \left (t \right ) = {\mathrm e}^{\frac {\left (-1+\sqrt {37}\right ) t}{2}} c_{2} +{\mathrm e}^{-\frac {\left (1+\sqrt {37}\right ) t}{2}} c_{1} +\frac {1}{3} \]
✓ Solution by Mathematica
Time used: 0.67 (sec). Leaf size: 192
DSolve[{x'[t]==-3*x[t]+3*y[t],y'[t]==x[t]+2*y[t]-1},{x[t],y[t]},t,IncludeSingularSolutions -> True]
\begin{align*} x(t)\to \frac {1}{222} e^{-\frac {1}{2} \left (1+\sqrt {37}\right ) t} \left (74 e^{\frac {1}{2} \left (1+\sqrt {37}\right ) t}-3 \left (\left (5 \sqrt {37}-37\right ) c_1-6 \sqrt {37} c_2\right ) e^{\sqrt {37} t}+3 \left (\left (37+5 \sqrt {37}\right ) c_1-6 \sqrt {37} c_2\right )\right ) y(t)\to \frac {1}{222} e^{-\frac {1}{2} \left (1+\sqrt {37}\right ) t} \left (74 e^{\frac {1}{2} \left (1+\sqrt {37}\right ) t}+3 \left (2 \sqrt {37} c_1+\left (37+5 \sqrt {37}\right ) c_2\right ) e^{\sqrt {37} t}-3 \left (2 \sqrt {37} c_1+\left (5 \sqrt {37}-37\right ) c_2\right )\right ) \end{align*}