3.19 problem 19

Internal problem ID [6154]

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: 19.
ODE order: 2.
ODE degree: 1.

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

Solve \begin {gather*} \boxed {y^{\prime \prime }+3 x y^{\prime }+7 y=0} \end {gather*} With the expansion point for the power series method at \(x = 0\).

Solution by Maple

Time used: 0.0 (sec). Leaf size: 44

Order:=8; 
dsolve(diff(y(x),x$2)+3*x*diff(y(x),x)+7*y(x)=0,y(x),type='series',x=0);
 

\[ y \relax (x ) = \left (1-\frac {7}{2} x^{2}+\frac {91}{24} x^{4}-\frac {1729}{720} x^{6}\right ) y \relax (0)+\left (x -\frac {5}{3} x^{3}+\frac {4}{3} x^{5}-\frac {44}{63} x^{7}\right ) D\relax (y )\relax (0)+O\left (x^{8}\right ) \]

Solution by Mathematica

Time used: 0.001 (sec). Leaf size: 56

AsymptoticDSolveValue[y''[x]+3*x*y'[x]+7*y[x]==0,y[x],{x,0,7}]
 

\[ y(x)\to c_2 \left (-\frac {44 x^7}{63}+\frac {4 x^5}{3}-\frac {5 x^3}{3}+x\right )+c_1 \left (-\frac {1729 x^6}{720}+\frac {91 x^4}{24}-\frac {7 x^2}{2}+1\right ) \]