13.3 problem 20

Internal problem ID [14639]

Book: INTRODUCTORY DIFFERENTIAL EQUATIONS. Martha L. Abell, James P. Braselton. Fourth edition 2014. ElScAe. 2014
Section: Chapter 4. Higher Order Equations. Exercises 4.5, page 175
Problem number: 20.
ODE order: 3.
ODE degree: 1.

CAS Maple gives this as type [[_3rd_order, _missing_x]]

\[ \boxed {8 y^{\prime \prime \prime }+y^{\prime \prime }=0} \]

Solution by Maple

Time used: 0.0 (sec). Leaf size: 15

dsolve(8*diff(y(t),t$3)+diff(y(t),t$2)=0,y(t), singsol=all)
 

\[ y \left (t \right ) = c_{1} +t c_{2} +c_{3} {\mathrm e}^{-\frac {t}{8}} \]

Solution by Mathematica

Time used: 0.059 (sec). Leaf size: 23

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

\[ y(t)\to 64 c_1 e^{-t/8}+c_3 t+c_2 \]