15.12 problem 8

Internal problem ID [1360]

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 II. Exercises 7.6. Page 374
Problem number: 8.
ODE order: 2.
ODE degree: 1.

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

Solve \begin {gather*} \boxed {x^{2} \left (1+2 x \right ) y^{\prime \prime }+x \left (3 x^{2}+14 x +5\right ) y^{\prime }+\left (12 x^{2}+18 x +4\right ) y=0} \end {gather*} With the expansion point for the power series method at \(x = 0\).

Solution by Maple

Time used: 0.015 (sec). Leaf size: 79

Order:=8; 
dsolve(x^2*(1+2*x)*diff(y(x),x$2)+x*(5+14*x+3*x^2)*diff(y(x),x)+(4+18*x+12*x^2)*y(x)=0,y(x),type='series',x=0);
 

\[ y \relax (x ) = \frac {\left (c_{2} \ln \relax (x )+c_{1}\right ) \left (1-2 x +\frac {5}{2} x^{2}-3 x^{3}+\frac {33}{8} x^{4}-\frac {129}{20} x^{5}+\frac {867}{80} x^{6}-\frac {1059}{56} x^{7}+\mathrm {O}\left (x^{8}\right )\right )+\left (\frac {3}{4} x^{2}-\frac {13}{6} x^{3}+\frac {407}{96} x^{4}-\frac {9047}{1200} x^{5}+\frac {63851}{4800} x^{6}-\frac {559033}{23520} x^{7}+\mathrm {O}\left (x^{8}\right )\right ) c_{2}}{x^{2}} \]

Solution by Mathematica

Time used: 0.016 (sec). Leaf size: 157

AsymptoticDSolveValue[x^2*(1+2*x)*y''[x]+x*(5+14*x+3*x^2)*y'[x]+(4+18*x+12*x^2)*y[x]==0,y[x],{x,0,7}]
 

\[ y(x)\to \frac {c_1 \left (-\frac {1059 x^7}{56}+\frac {867 x^6}{80}-\frac {129 x^5}{20}+\frac {33 x^4}{8}-3 x^3+\frac {5 x^2}{2}-2 x+1\right )}{x^2}+c_2 \left (\frac {-\frac {559033 x^7}{23520}+\frac {63851 x^6}{4800}-\frac {9047 x^5}{1200}+\frac {407 x^4}{96}-\frac {13 x^3}{6}+\frac {3 x^2}{4}}{x^2}+\frac {\left (-\frac {1059 x^7}{56}+\frac {867 x^6}{80}-\frac {129 x^5}{20}+\frac {33 x^4}{8}-3 x^3+\frac {5 x^2}{2}-2 x+1\right ) \log (x)}{x^2}\right ) \]