29.3 problem 2(c)

Internal problem ID [6531]

Book: Differential Equations: Theory, Technique, and Practice by George Simmons, Steven Krantz. McGraw-Hill NY. 2007. 1st Edition.
Section: Chapter 10. Systems of First-Order Equations. Section A. Drill exercises. Page 400
Problem number: 2(c).
ODE order: 1.
ODE degree: 1.

Solve \begin {align*} x^{\prime }\left (t \right )&=-3 x \left (t \right )+\sqrt {2}\, y \left (t \right )\\ y^{\prime }\left (t \right )&=\sqrt {2}\, x \left (t \right )-2 y \left (t \right ) \end {align*}

Solution by Maple

Time used: 0.062 (sec). Leaf size: 41

dsolve([diff(x(t),t)=-3*x(t)+sqrt(2)*y(t),diff(y(t),t)=sqrt(2)*x(t)-2*y(t)],[x(t), y(t)], singsol=all)
 

\[ x \left (t \right ) = -\frac {\left (2 c_{1} {\mathrm e}^{-4 t}-{\mathrm e}^{-t} c_{2} \right ) \sqrt {2}}{2} \] \[ y \left (t \right ) = c_{1} {\mathrm e}^{-4 t}+{\mathrm e}^{-t} c_{2} \]

Solution by Mathematica

Time used: 0.004 (sec). Leaf size: 80

DSolve[{x'[t]==-3*x[t]+Sqrt[2]*y[t],y'[t]==Sqrt[2]*x[t]-2*y[t]},{x[t],y[t]},t,IncludeSingularSolutions -> True]
 

\begin{align*} x(t)\to \frac {1}{3} e^{-4 t} \left (c_1 \left (e^{3 t}+2\right )+\sqrt {2} c_2 \left (e^{3 t}-1\right )\right ) y(t)\to \frac {1}{3} e^{-4 t} \left (\sqrt {2} c_1 \left (e^{3 t}-1\right )+c_2 \left (2 e^{3 t}+1\right )\right ) \end{align*}