64.2.4 problem 3(a)

Internal problem ID [13193]
Book : Differential Equations by Shepley L. Ross. Third edition. John Willey. New Delhi. 2004.
Section : Chapter 1, section 1.3. Exercises page 22
Problem number : 3(a)
Date solved : Monday, March 31, 2025 at 07:36:44 AM
CAS classification : [[_2nd_order, _missing_x]]

\begin{align*} y^{\prime \prime }-y^{\prime }-12 y&=0 \end{align*}

With initial conditions

\begin{align*} y \left (0\right )&=5\\ y^{\prime }\left (0\right )&=6 \end{align*}

✓ Maple. Time used: 0.049 (sec). Leaf size: 17

ode:=diff(diff(y(x),x),x)-diff(y(x),x)-12*y(x) = 0; 
ic:=y(0) = 5, D(y)(0) = 6; 
dsolve([ode,ic],y(x), singsol=all);
 

\[ y = 2 \,{\mathrm e}^{-3 x}+3 \,{\mathrm e}^{4 x} \]

✓ Mathematica. Time used: 0.014 (sec). Leaf size: 20

ode=D[y[x],{x,2}]-D[y[x],x]-12*y[x]==0; 
ic={y[0]==5,Derivative[1][y][0] ==6}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 

\[ y(x)\to e^{-3 x} \left (3 e^{7 x}+2\right ) \]

✓ Sympy. Time used: 0.180 (sec). Leaf size: 15

from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(-12*y(x) - Derivative(y(x), x) + Derivative(y(x), (x, 2)),0) 
ics = {y(0): 5, Subs(Derivative(y(x), x), x, 0): 6} 
dsolve(ode,func=y(x),ics=ics)
 

\[ y{\left (x \right )} = 3 e^{4 x} + 2 e^{- 3 x} \]