18.5 problem 3(a)

Internal problem ID [11535]

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: 3(a).
ODE order: 1.
ODE degree: 1.

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

Solution by Maple

Time used: 0.016 (sec). Leaf size: 24

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

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

Solution by Mathematica

Time used: 0.01 (sec). Leaf size: 33

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

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