9.12 problem 22

Internal problem ID [14456]

Book: INTRODUCTORY DIFFERENTIAL EQUATIONS. Martha L. Abell, James P. Braselton. Fourth edition 2014. ElScAe. 2014
Section: Chapter 4. Higher Order Equations. Exercises 4.1, page 141
Problem number: 22.
ODE order: 2.
ODE degree: 1.

CAS Maple gives this as type [[_2nd_order, _missing_x]]

\[ \boxed {y^{\prime \prime }+6 y^{\prime }+18 y=0} \]

Solution by Maple

Time used: 0.0 (sec). Leaf size: 22

dsolve(diff(y(t),t$2)+6*diff(y(t),t)+18*y(t)=0,y(t), singsol=all)
 

\[ y \left (t \right ) = {\mathrm e}^{-3 t} \left (c_{1} \sin \left (3 t \right )+\cos \left (3 t \right ) c_{2} \right ) \]

Solution by Mathematica

Time used: 0.017 (sec). Leaf size: 26

DSolve[y''[t]+6*y'[t]+18*y[t]==0,y[t],t,IncludeSingularSolutions -> True]
 

\[ y(t)\to e^{-3 t} (c_2 \cos (3 t)+c_1 \sin (3 t)) \]