54.3.4 problem 4

Internal problem ID [8560]
Book : Elementary differential equations. Rainville, Bedient, Bedient. Prentice Hall. NJ. 8th edition. 1997.
Section : CHAPTER 17. Power series solutions. 17.5. Solutions Near an Ordinary Point. Exercises page 355
Problem number : 4
Date solved : Wednesday, March 05, 2025 at 06:09:37 AM
CAS classification : [[_2nd_order, _exact, _linear, _homogeneous]]

\begin{align*} \left (4 x^{2}+1\right ) y^{\prime \prime }-8 y&=0 \end{align*}

Using series method with expansion around

\begin{align*} 0 \end{align*}

✓ Maple. Time used: 0.003 (sec). Leaf size: 39

Order:=8; 
ode:=(4*x^2+1)*diff(diff(y(x),x),x)-8*y(x) = 0; 
dsolve(ode,y(x),type='series',x=0);
 

\[ y = \left (4 x^{2}+1\right ) y \left (0\right )+\left (x +\frac {4}{3} x^{3}-\frac {16}{15} x^{5}+\frac {64}{35} x^{7}\right ) y^{\prime }\left (0\right )+O\left (x^{8}\right ) \]

✓ Mathematica. Time used: 0.002 (sec). Leaf size: 40

ode=(1+4*x^2)*D[y[x],{x,2}]-8*y[x]==0; 
ic={}; 
AsymptoticDSolveValue[{ode,ic},y[x],{x,0,7}]
 

\[ y(x)\to c_1 \left (4 x^2+1\right )+c_2 \left (\frac {64 x^7}{35}-\frac {16 x^5}{15}+\frac {4 x^3}{3}+x\right ) \]

✓ Sympy. Time used: 0.802 (sec). Leaf size: 32

from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq((4*x**2 + 1)*Derivative(y(x), (x, 2)) - 8*y(x),0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics,hint="2nd_power_series_ordinary",x0=0,n=8)
 

\[ y{\left (x \right )} = C_{2} \left (4 x^{2} + 1\right ) + C_{1} x \left (- \frac {16 x^{4}}{15} + \frac {4 x^{2}}{3} + 1\right ) + O\left (x^{8}\right ) \]