1.9 problem 20

Internal problem ID [820]

Book: Elementary differential equations and boundary value problems, 11th ed., Boyce, DiPrima, Meade
Section: Chapter 4.1, Higher order linear differential equations. General theory. page 173
Problem number: 20.
ODE order: 3.
ODE degree: 1.

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

\[ \boxed {\left (2-t \right ) y^{\prime \prime \prime }+\left (2 t -3\right ) y^{\prime \prime }-t y^{\prime }+y=0} \]

Solution by Maple

Time used: 0.015 (sec). Leaf size: 17

dsolve([(2-t)*diff(y(t),t$3)+(2*t-3)*diff(y(t),t$2)-t*diff(y(t),t)+y(t)=0,exp(t)],y(t), singsol=all)
 

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

Solution by Mathematica

Time used: 0.079 (sec). Leaf size: 28

DSolve[(2-t)*y'''[t]+(2*t-3)*y''[t]-t*y'[t]+y[t]==0,y[t],t,IncludeSingularSolutions -> True]
 

\[ y(t)\to t \left (c_2 e^t+c_1\right )+(c_3-4 c_2) e^t \]