74.13.5 problem 22

Internal problem ID [16292]
Book : INTRODUCTORY DIFFERENTIAL EQUATIONS. Martha L. Abell, James P. Braselton. Fourth edition 2014. ElScAe. 2014
Section : Chapter 4. Higher Order Equations. Exercises 4.5, page 175
Problem number : 22
Date solved : Thursday, March 13, 2025 at 08:10:05 AM
CAS classification : [[_3rd_order, _missing_x]]

\begin{align*} y^{\prime \prime \prime }-2 y^{\prime \prime }-y^{\prime }+2 y&=0 \end{align*}

✓ Maple. Time used: 0.006 (sec). Leaf size: 21

ode:=diff(diff(diff(y(t),t),t),t)-2*diff(diff(y(t),t),t)-diff(y(t),t)+2*y(t) = 0; 
dsolve(ode,y(t), singsol=all);
 

\[ y = {\mathrm e}^{-t} c_{1} +c_{2} {\mathrm e}^{2 t}+c_{3} {\mathrm e}^{t} \]

✓ Mathematica. Time used: 0.003 (sec). Leaf size: 28

ode=D[ y[t],{t,3}]-2*D[y[t],{t,2}]-D[y[t],t]+2*y[t]==0; 
ic={}; 
DSolve[{ode,ic},y[t],t,IncludeSingularSolutions->True]
 

\[ y(t)\to c_1 e^{-t}+c_2 e^t+c_3 e^{2 t} \]

✓ Sympy. Time used: 0.152 (sec). Leaf size: 19

from sympy import * 
t = symbols("t") 
y = Function("y") 
ode = Eq(2*y(t) - Derivative(y(t), t) - 2*Derivative(y(t), (t, 2)) + Derivative(y(t), (t, 3)),0) 
ics = {} 
dsolve(ode,func=y(t),ics=ics)
 

\[ y{\left (t \right )} = C_{1} e^{- t} + C_{2} e^{t} + C_{3} e^{2 t} \]