72.15.14 problem 25

Internal problem ID [14895]
Book : DIFFERENTIAL EQUATIONS by Paul Blanchard, Robert L. Devaney, Glen R. Hall. 4th edition. Brooks/Cole. Boston, USA. 2012
Section : Chapter 3. Linear Systems. Review Exercises for chapter 3. page 376
Problem number : 25
Date solved : Tuesday, January 28, 2025 at 07:18:19 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 )&=1\\ y^{\prime }\left (0\right )&=1 \end{align*}

Solution by Maple

Time used: 0.008 (sec). Leaf size: 14

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

Solution by Mathematica

Time used: 0.014 (sec). Leaf size: 16

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