7.3 problem 11

Internal problem ID [5937]

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. 7.4.1 DERIVATIVES OF A TRANSFORM. Page 309
Problem number: 11.
ODE order: 2.
ODE degree: 1.

CAS Maple gives this as type [[_2nd_order, _linear, _nonhomogeneous]]

Solve \begin {gather*} \boxed {y^{\prime \prime }+9 y-\cos \left (3 t \right )=0} \end {gather*} With initial conditions \begin {align*} [y \relax (0) = 2, y^{\prime }\relax (0) = 5] \end {align*}

Solution by Maple

Time used: 0.012 (sec). Leaf size: 20

dsolve([diff(y(t),t$2)+9*y(t)=cos(3*t),y(0) = 2, D(y)(0) = 5],y(t), singsol=all)
 

\[ y \relax (t ) = \frac {\left (10+t \right ) \sin \left (3 t \right )}{6}+2 \cos \left (3 t \right ) \]

Solution by Mathematica

Time used: 0.018 (sec). Leaf size: 23

DSolve[{y''[t]+9*y[t]==Cos[3*t],{y[0]==2,y'[0]==5}},y[t],t,IncludeSingularSolutions -> True]
 

\begin{align*} y(t)\to \frac {1}{6} (t+10) \sin (3 t)+2 \cos (3 t) \\ \end{align*}