9.15 problem 26

Internal problem ID [14459]

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: 26.
ODE order: 2.
ODE degree: 1.

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

\[ \boxed {y^{\prime \prime }+6 y^{\prime }+8 y=0} \] Given that one solution of the ode is \begin {align*} y_1 &= {\mathrm e}^{-2 t} \end {align*}

Solution by Maple

Time used: 0.0 (sec). Leaf size: 17

dsolve([diff(y(t),t$2)+6*diff(y(t),t)+8*y(t)=0,exp(-2*t)],singsol=all)
 

\[ y \left (t \right ) = {\mathrm e}^{-2 t} c_{1} +c_{2} {\mathrm e}^{-4 t} \]

Solution by Mathematica

Time used: 0.013 (sec). Leaf size: 22

DSolve[y''[t]+6*y'[t]+8*y[t]==0,y[t],t,IncludeSingularSolutions -> True]
 

\[ y(t)\to e^{-4 t} \left (c_2 e^{2 t}+c_1\right ) \]