8.7.9 problem 9

Internal problem ID [815]
Book : Differential equations and linear algebra, 3rd ed., Edwards and Penney
Section : Section 5.1, second order linear equations. Page 299
Problem number : 9
Date solved : Monday, January 27, 2025 at 03:09:11 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 )&=2\\ y^{\prime }\left (0\right )&=-1 \end{align*}

Solution by Maple

Time used: 0.005 (sec). Leaf size: 12

dsolve([diff(y(x),x$2)+2*diff(y(x),x)+y(x)=0,y(0) = 2, D(y)(0) = -1],y(x), singsol=all)
 
\[ y = {\mathrm e}^{-x} \left (x +2\right ) \]

Solution by Mathematica

Time used: 0.013 (sec). Leaf size: 14

DSolve[{D[y[x],{x,2}]+2*D[y[x],x]+y[x]==0,{y[0]==2,Derivative[1][y][0] ==-1}},y[x],x,IncludeSingularSolutions -> True]
 
\[ y(x)\to e^{-x} (x+2) \]