18.4 problem 2(d)

Internal problem ID [11544]

Book: A First Course in Differential Equations by J. David Logan. Third Edition. Springer-Verlag, NY. 2015.
Section: Chapter 4, Linear Systems. Exercises page 190
Problem number: 2(d).
ODE order: 1.
ODE degree: 1.

Solve \begin {align*} x^{\prime }&=4 y \left (t \right )\\ y^{\prime }\left (t \right )&=2 y \left (t \right ) \end {align*}

Solution by Maple

Time used: 0.078 (sec). Leaf size: 23

dsolve([diff(x(t),t)=4*y(t),diff(y(t),t)=2*y(t)],[x(t), y(t)], singsol=all)
 

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

Solution by Mathematica

Time used: 0.067 (sec). Leaf size: 65

DSolve[{x'[t]==4*x[t],y'[t]==2*y[t]},{x[t],y[t]},t,IncludeSingularSolutions -> True]
 

\begin{align*} x(t)\to c_1 e^{4 t} y(t)\to c_2 e^{2 t} x(t)\to c_1 e^{4 t} y(t)\to 0 x(t)\to 0 y(t)\to c_2 e^{2 t} x(t)\to 0 y(t)\to 0 \end{align*}