9.9 problem 9

Internal problem ID [661]

Book: Elementary differential equations and boundary value problems, 10th ed., Boyce and DiPrima
Section: Chapter 3, Second order linear equations, 3.4 Repeated roots, reduction of order , page 172
Problem number: 9.
ODE order: 2.
ODE degree: 1.

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

Solve \begin {gather*} \boxed {25 y^{\prime \prime }-20 y^{\prime }+4 y=0} \end {gather*}

Solution by Maple

Time used: 0.016 (sec). Leaf size: 18

dsolve(25*diff(y(x),x$2)-20*diff(y(x),x)+4*y(x) = 0,y(x), singsol=all)
 

\[ y \relax (x ) = c_{1} {\mathrm e}^{\frac {2 x}{5}}+c_{2} {\mathrm e}^{\frac {2 x}{5}} x \]

Solution by Mathematica

Time used: 0.003 (sec). Leaf size: 20

DSolve[25*y''[x]-20*y'[x]+4*y[x]==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to e^{2 x/5} (c_2 x+c_1) \\ \end{align*}