16.40 problem 36

Internal problem ID [1452]

Book: Elementary differential equations with boundary value problems. William F. Trench. Brooks/Cole 2001
Section: Chapter 7 Series Solutions of Linear Second Equations. 7.6 THE METHOD OF FROBENIUS III. Exercises 7.7. Page 389
Problem number: 36.
ODE order: 2.
ODE degree: 1.

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

Solve \begin {gather*} \boxed {4 x^{2} \left (x^{2}+1\right ) y^{\prime \prime }+8 y^{\prime } x -\left (-x^{2}+35\right ) y=0} \end {gather*} With the expansion point for the power series method at \(x = 0\).

Solution by Maple

Time used: 0.016 (sec). Leaf size: 35

Order:=6; 
dsolve(4*x^2*(1+x^2)*diff(y(x),x$2)+8*x*diff(y(x),x)-(35-x^2)*y(x)=0,y(x),type='series',x=0);
 

\[ y \relax (x ) = \frac {c_{1} x^{6} \left (1-\frac {1}{4} x^{2}+\frac {1}{10} x^{4}+\mathrm {O}\left (x^{6}\right )\right )+c_{2} \left (-86400-172800 x^{2}-86400 x^{4}+\mathrm {O}\left (x^{6}\right )\right )}{x^{\frac {7}{2}}} \]

Solution by Mathematica

Time used: 0.015 (sec). Leaf size: 52

AsymptoticDSolveValue[4*x^2*(1+x^2)*y''[x]+8*x*y'[x]-(35-x^2)*y[x]==0,y[x],{x,0,5}]
 

\[ y(x)\to c_1 \left (\frac {2}{x^{3/2}}+\frac {1}{x^{7/2}}+\sqrt {x}\right )+c_2 \left (\frac {x^{13/2}}{10}-\frac {x^{9/2}}{4}+x^{5/2}\right ) \]