5.10 problem 40

Internal problem ID [6665]

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. 7.2.2 TRANSFORMS OF DERIVATIVES Page 289
Problem number: 40.
ODE order: 3.
ODE degree: 1.

CAS Maple gives this as type [[_3rd_order, _linear, _nonhomogeneous]]

\[ \boxed {y^{\prime \prime \prime }+2 y^{\prime \prime }-y^{\prime }-2 y=\sin \left (3 t \right )} \] With initial conditions \begin {align*} [y \left (0\right ) = 0, y^{\prime }\left (0\right ) = 0, y^{\prime \prime }\left (0\right ) = 1] \end {align*}

Solution by Maple

Time used: 1.875 (sec). Leaf size: 31

dsolve([diff(y(t),t$3)+2*diff(y(t),t$2)-diff(y(t),t)-2*y(t)=sin(3*t),y(0) = 0, D(y)(0) = 0, (D@@2)(y)(0) = 1],y(t), singsol=all)
 

\[ y \left (t \right ) = \frac {3 \cos \left (3 t \right )}{130}-\frac {\sin \left (3 t \right )}{65}-\frac {13 \cosh \left (t \right )}{30}+\frac {13 \sinh \left (t \right )}{15}+\frac {16 \,{\mathrm e}^{-2 t}}{39} \]

Solution by Mathematica

Time used: 0.072 (sec). Leaf size: 42

DSolve[{y'''[t]+2*y''[t]-y'[t]-2*y[t]==Sin[3*t],{y[0]==0,y'[0]==0,y''[0]==1}},y[t],t,IncludeSingularSolutions -> True]
 

\[ y(t)\to \frac {1}{780} \left (e^{-2 t} \left (-507 e^t+169 e^{3 t}+320\right )-12 \sin (3 t)+18 \cos (3 t)\right ) \]