6.5 problem Problem 27

Internal problem ID [2220]

Book: Differential equations and linear algebra, Stephen W. Goode and Scott A Annin. Fourth edition, 2015
Section: Chapter 8, Linear differential equations of order n. Section 8.1, General Theory for Linear Differential Equations. page 502
Problem number: Problem 27.
ODE order: 3.
ODE degree: 1.

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

Solve \begin {gather*} \boxed {y^{\prime \prime \prime }-3 y^{\prime \prime }-y^{\prime }+3 y=0} \end {gather*}

Solution by Maple

Time used: 0.005 (sec). Leaf size: 21

dsolve(diff(y(x),x$3)-3*diff(y(x),x$2)-diff(y(x),x)+3*y(x)=0,y(x), singsol=all)
 

\[ y \relax (x ) = {\mathrm e}^{-x} c_{1}+c_{2} {\mathrm e}^{3 x}+c_{3} {\mathrm e}^{x} \]

Solution by Mathematica

Time used: 0.003 (sec). Leaf size: 28

DSolve[y'''[x]-3*y''[x]-y'[x]+3*y[x]==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to c_1 e^{-x}+c_2 e^x+c_3 e^{3 x} \\ \end{align*}