40.8.10 problem 25

Internal problem ID [6710]
Book : Schaums Outline. Theory and problems of Differential Equations, 1st edition. Frank Ayres. McGraw Hill 1952
Section : Chapter 13. Homogeneous Linear equations with constant coefficients. Supplemetary problems. Page 86
Problem number : 25
Date solved : Wednesday, March 05, 2025 at 02:39:53 AM
CAS classification : [[_high_order, _missing_x]]

\begin{align*} y^{\left (6\right )}+9 y^{\prime \prime \prime \prime }+24 y^{\prime \prime }+16 y&=0 \end{align*}

Maple. Time used: 0.002 (sec). Leaf size: 33
ode:=diff(diff(diff(diff(diff(diff(y(x),x),x),x),x),x),x)+9*diff(diff(diff(diff(y(x),x),x),x),x)+24*diff(diff(y(x),x),x)+16*y(x) = 0; 
dsolve(ode,y(x), singsol=all);
 
\[ y = \left (c_6 x +c_4 \right ) \cos \left (2 x \right )+\left (c_5 x +c_3 \right ) \sin \left (2 x \right )+\sin \left (x \right ) c_1 +\cos \left (x \right ) c_2 \]
Mathematica. Time used: 0.004 (sec). Leaf size: 40
ode=D[y[x],{x,6}]+9*D[y[x],{x,4}]+24*D[y[x],{x,2}]+16*y[x]==0; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 
\[ y(x)\to (c_2 x+c_1) \cos (2 x)+c_6 \sin (x)+\cos (x) (2 (c_4 x+c_3) \sin (x)+c_5) \]
Sympy. Time used: 0.155 (sec). Leaf size: 32
from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(16*y(x) + 24*Derivative(y(x), (x, 2)) + 9*Derivative(y(x), (x, 4)) + Derivative(y(x), (x, 6)),0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 
\[ y{\left (x \right )} = C_{5} \sin {\left (x \right )} + C_{6} \cos {\left (x \right )} + \left (C_{1} + C_{2} x\right ) \sin {\left (2 x \right )} + \left (C_{3} + C_{4} x\right ) \cos {\left (2 x \right )} \]