2.20 problem 20

Internal problem ID [4822]

Book: A FIRST COURSE IN DIFFERENTIAL EQUATIONS with Modeling Applications. Dennis G. Zill. 9th edition. Brooks/Cole. CA, USA.
Section: Chapter 6. SERIES SOLUTIONS OF LINEAR EQUATIONS. Exercises. 6.2 page 239
Problem number: 20.
ODE order: 2.
ODE degree: 1.

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

Solve \begin {gather*} \boxed {x^{2} y^{\prime \prime }-\left (x -\frac {2}{9}\right ) y=0} \end {gather*} With the expansion point for the power series method at \(x = 0\).

Solution by Maple

Time used: 0.028 (sec). Leaf size: 47

Order:=6; 
dsolve(x^2*diff(y(x),x$2)-(x-2/9)*y(x)=0,y(x),type='series',x=0);
 

\[ y \relax (x ) = c_{1} x^{\frac {1}{3}} \left (1+\frac {3}{2} x +\frac {9}{20} x^{2}+\frac {9}{160} x^{3}+\frac {27}{7040} x^{4}+\frac {81}{492800} x^{5}+\mathrm {O}\left (x^{6}\right )\right )+c_{2} x^{\frac {2}{3}} \left (1+\frac {3}{4} x +\frac {9}{56} x^{2}+\frac {9}{560} x^{3}+\frac {27}{29120} x^{4}+\frac {81}{2329600} x^{5}+\mathrm {O}\left (x^{6}\right )\right ) \]

Solution by Mathematica

Time used: 0.003 (sec). Leaf size: 90

AsymptoticDSolveValue[x^2*y''[x]-(x-2/9)*y[x]==0,y[x],{x,0,5}]
 

\[ y(x)\to c_2 \sqrt [3]{x} \left (\frac {81 x^5}{492800}+\frac {27 x^4}{7040}+\frac {9 x^3}{160}+\frac {9 x^2}{20}+\frac {3 x}{2}+1\right )+c_1 x^{2/3} \left (\frac {81 x^5}{2329600}+\frac {27 x^4}{29120}+\frac {9 x^3}{560}+\frac {9 x^2}{56}+\frac {3 x}{4}+1\right ) \]