73.12.24 problem 19.4 (h)

Internal problem ID [15297]
Book : Ordinary Differential Equations. An introduction to the fundamentals. Kenneth B. Howell. second edition. CRC Press. FL, USA. 2020
Section : Chapter 19. Arbitrary Homogeneous linear equations with constant coefficients. Additional exercises page 369
Problem number : 19.4 (h)
Date solved : Thursday, March 13, 2025 at 05:52:06 AM
CAS classification : [[_high_order, _missing_x]]

\begin{align*} 4 y^{\prime \prime \prime \prime }+15 y^{\prime \prime }-4 y&=0 \end{align*}

✓ Maple. Time used: 0.003 (sec). Leaf size: 29

ode:=4*diff(diff(diff(diff(y(x),x),x),x),x)+15*diff(diff(y(x),x),x)-4*y(x) = 0; 
dsolve(ode,y(x), singsol=all);
 

\[ y = c_{1} {\mathrm e}^{\frac {x}{2}}+{\mathrm e}^{-\frac {x}{2}} c_{2} +c_{3} \sin \left (2 x \right )+c_4 \cos \left (2 x \right ) \]

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

ode=4*D[y[x],{x,4}]+15*D[y[x],{x,2}]-4*y[x]==0; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 

\[ y(x)\to e^{-x/2} \left (c_4 e^x+c_3\right )+c_1 \cos (2 x)+c_2 \sin (2 x) \]

✓ Sympy. Time used: 0.099 (sec). Leaf size: 29

from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(-4*y(x) + 15*Derivative(y(x), (x, 2)) + 4*Derivative(y(x), (x, 4)),0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 

\[ y{\left (x \right )} = C_{1} e^{- \frac {x}{2}} + C_{2} e^{\frac {x}{2}} + C_{3} \sin {\left (2 x \right )} + C_{4} \cos {\left (2 x \right )} \]