67.3.4 problem Problem 5

Internal problem ID [13943]
Book : APPLIED DIFFERENTIAL EQUATIONS The Primary Course by Vladimir A. Dobrushkin. CRC Press 2015
Section : Chapter 5.5 Laplace transform. Homogeneous equations. Problems page 357
Problem number : Problem 5
Date solved : Wednesday, March 05, 2025 at 10:24:02 PM
CAS classification : [[_2nd_order, _missing_x]]

\begin{align*} y^{\prime \prime }-4 y^{\prime }+5 y&=0 \end{align*}

Using Laplace method With initial conditions

\begin{align*} y \left (0\right )&=0\\ y^{\prime }\left (0\right )&=3 \end{align*}

✓ Maple. Time used: 8.778 (sec). Leaf size: 12

ode:=diff(diff(y(t),t),t)-4*diff(y(t),t)+5*y(t) = 0; 
ic:=y(0) = 0, D(y)(0) = 3; 
dsolve([ode,ic],y(t),method='laplace');
 

\[ y = 3 \,{\mathrm e}^{2 t} \sin \left (t \right ) \]

✓ Mathematica. Time used: 0.016 (sec). Leaf size: 14

ode=D[y[t],{t,2}]-4*D[y[t],t]+5*y[t]==0; 
ic={y[0]==0,Derivative[1][y][0] ==3}; 
DSolve[{ode,ic},y[t],t,IncludeSingularSolutions->True]
 

\[ y(t)\to 3 e^{2 t} \sin (t) \]

✓ Sympy. Time used: 0.184 (sec). Leaf size: 12

from sympy import * 
t = symbols("t") 
y = Function("y") 
ode = Eq(5*y(t) - 4*Derivative(y(t), t) + Derivative(y(t), (t, 2)),0) 
ics = {y(0): 0, Subs(Derivative(y(t), t), t, 0): 3} 
dsolve(ode,func=y(t),ics=ics)
 

\[ y{\left (t \right )} = 3 e^{2 t} \sin {\left (t \right )} \]