52.8.5 problem 5

Internal problem ID [8369]
Book : DIFFERENTIAL EQUATIONS with Boundary Value Problems. DENNIS G. ZILL, WARREN S. WRIGHT, MICHAEL R. CULLEN. Brooks/Cole. Boston, MA. 2013. 8th edition.
Section : CHAPTER 7 THE LAPLACE TRANSFORM. EXERCISES 7.5. Page 315
Problem number : 5
Date solved : Monday, January 27, 2025 at 03:49:41 PM
CAS classification : [[_2nd_order, _linear, _nonhomogeneous]]

\begin{align*} y^{\prime \prime }+y&=\delta \left (t -\frac {\pi }{2}\right )+\delta \left (t -\frac {3 \pi }{2}\right ) \end{align*}

Using Laplace method With initial conditions

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

Solution by Maple

Time used: 0.744 (sec). Leaf size: 22

dsolve([diff(y(t),t$2)+y(t)=Dirac(t-1/2*Pi)+Dirac(t-3/2*Pi),y(0) = 0, D(y)(0) = 0],y(t), singsol=all)
 
\[ y = \left (\operatorname {Heaviside}\left (t -\frac {3 \pi }{2}\right )-\operatorname {Heaviside}\left (t -\frac {\pi }{2}\right )\right ) \cos \left (t \right ) \]

Solution by Mathematica

Time used: 0.044 (sec). Leaf size: 27

DSolve[{D[y[t],{t,2}]+y[t]==DiracDelta[t-1/2*Pi]+DiracDelta[t-3/2*Pi],{y[0]==0,Derivative[1][y][0] ==0}},y[t],t,IncludeSingularSolutions -> True]
 
\[ y(t)\to (\theta (2 t-3 \pi )-\theta (2 t-\pi )) \cos (t) \]