6.8.4 problem 3c

Internal problem ID [1740]
Book : Elementary differential equations with boundary value problems. William F. Trench. Brooks/Cole 2001
Section : Chapter 5 linear second order equations. Section 5.1 Homogeneous linear equations. Page 203
Problem number : 3c
Date solved : Tuesday, September 30, 2025 at 05:18:52 AM
CAS classification : [[_2nd_order, _missing_x]]

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

With initial conditions

\begin{align*} y \left (0\right )&=7 \\ y^{\prime }\left (0\right )&=4 \\ \end{align*}

✓ Maple. Time used: 0.043 (sec). Leaf size: 12

ode:=diff(diff(y(x),x),x)-2*diff(y(x),x)+y(x) = 0; 
ic:=[y(0) = 7, D(y)(0) = 4]; 
dsolve([ode,op(ic)],y(x), singsol=all);
 

\[ y = {\mathrm e}^{x} \left (7-3 x \right ) \]

✓ Mathematica. Time used: 0.007 (sec). Leaf size: 14

ode=D[y[x],{x,2}]-2*D[y[x],x]+y[x]==0; 
ic={y[0]==7,Derivative[1][y][0] ==4}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 

\begin{align*} y(x)&\to e^x (7-3 x) \end{align*}

✓ Sympy. Time used: 0.120 (sec). Leaf size: 10

from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(y(x) - 2*Derivative(y(x), x) + Derivative(y(x), (x, 2)),0) 
ics = {y(0): 7, Subs(Derivative(y(x), x), x, 0): 4} 
dsolve(ode,func=y(x),ics=ics)
 

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