80.5.30 problem C 6

Internal problem ID [21251]
Book : A Textbook on Ordinary Differential Equations by Shair Ahmad and Antonio Ambrosetti. Second edition. ISBN 978-3-319-16407-6. Springer 2015
Section : Chapter 5. Second order equations. Excercise 5.9 at page 119
Problem number : C 6
Date solved : Thursday, October 02, 2025 at 07:27:20 PM
CAS classification : [[_2nd_order, _with_linear_symmetries]]

\begin{align*} x^{\prime \prime }-x&=3 \,{\mathrm e}^{2 t} \end{align*}
Maple. Time used: 0.003 (sec). Leaf size: 19
ode:=diff(diff(x(t),t),t)-x(t) = 3*exp(2*t); 
dsolve(ode,x(t), singsol=all);
 
\[ x = {\mathrm e}^{-t} c_2 +{\mathrm e}^{t} c_1 +{\mathrm e}^{2 t} \]
Mathematica. Time used: 0.01 (sec). Leaf size: 25
ode=D[x[t],{t,2}]-x[t]==3*Exp[2*t]; 
ic={}; 
DSolve[{ode,ic},x[t],t,IncludeSingularSolutions->True]
 
\begin{align*} x(t)&\to e^{2 t}+c_1 e^t+c_2 e^{-t} \end{align*}
Sympy. Time used: 0.037 (sec). Leaf size: 17
from sympy import * 
t = symbols("t") 
x = Function("x") 
ode = Eq(-x(t) - 3*exp(2*t) + Derivative(x(t), (t, 2)),0) 
ics = {} 
dsolve(ode,func=x(t),ics=ics)
 
\[ x{\left (t \right )} = C_{1} e^{- t} + C_{2} e^{t} + e^{2 t} \]