32.7.24 problem Exercise 20.25, page 220

Internal problem ID [5939]
Book : Ordinary Differential Equations, By Tenenbaum and Pollard. Dover, NY 1963
Section : Chapter 4. Higher order linear differential equations. Lesson 20. Constant coefficients
Problem number : Exercise 20.25, page 220
Date solved : Monday, January 27, 2025 at 01:27:49 PM
CAS classification : [[_high_order, _missing_x]]

\begin{align*} y^{\prime \prime \prime \prime }+5 y^{\prime \prime }+6 y&=0 \end{align*}

Solution by Maple

Time used: 0.003 (sec). Leaf size: 37

dsolve(diff(y(x),x$4)+5*diff(y(x),x$2)+6*y(x)=0,y(x), singsol=all)
 
\[ y \left (x \right ) = c_{1} \sin \left (\sqrt {2}\, x \right )+c_{2} \cos \left (\sqrt {2}\, x \right )+c_3 \sin \left (\sqrt {3}\, x \right )+c_4 \cos \left (\sqrt {3}\, x \right ) \]

Solution by Mathematica

Time used: 0.005 (sec). Leaf size: 50

DSolve[D[y[x],{x,4}]+5*D[y[x],{x,2}]+6*y[x]==0,y[x],x,IncludeSingularSolutions -> True]
 
\[ y(x)\to c_3 \cos \left (\sqrt {2} x\right )+c_1 \cos \left (\sqrt {3} x\right )+c_4 \sin \left (\sqrt {2} x\right )+c_2 \sin \left (\sqrt {3} x\right ) \]