27.2 problem 38.2

Internal problem ID [13702]

Book: Ordinary Differential Equations. An introduction to the fundamentals. Kenneth B. Howell. second edition. CRC Press. FL, USA. 2020
Section: Chapter 38. Systems of differential equations. A starting point. Additional Exercises. page 786
Problem number: 38.2.
ODE order: 1.
ODE degree: 1.

Solve \begin {align*} x^{\prime }\left (t \right )&=4 x \left (t \right )-3 y \left (t \right )\\ y^{\prime }\left (t \right )&=6 x \left (t \right )-7 y \left (t \right ) \end {align*}

Solution by Maple

Time used: 0.016 (sec). Leaf size: 36

dsolve([diff(x(t),t)=4*x(t)-3*y(t),diff(y(t),t)=6*x(t)-7*y(t)],[x(t), y(t)], singsol=all)
 

\begin{align*} x \left (t \right ) = \frac {3 c_{1} {\mathrm e}^{2 t}}{2}+\frac {c_{2} {\mathrm e}^{-5 t}}{3} y \left (t \right ) = c_{1} {\mathrm e}^{2 t}+c_{2} {\mathrm e}^{-5 t} \end{align*}

Solution by Mathematica

Time used: 0.003 (sec). Leaf size: 74

DSolve[{x'[t]==4*x[t]-3*y[t],y'[t]==6*x[t]-7*y[t]},{x[t],y[t]},t,IncludeSingularSolutions -> True]
 

\begin{align*} x(t)\to \frac {1}{7} e^{-5 t} \left (c_1 \left (9 e^{7 t}-2\right )-3 c_2 \left (e^{7 t}-1\right )\right ) y(t)\to \frac {1}{7} e^{-5 t} \left (6 c_1 \left (e^{7 t}-1\right )+c_2 \left (9-2 e^{7 t}\right )\right ) \end{align*}