18.2 problem 1(b)

Internal problem ID [5675]

Book: Differential Equations: Theory, Technique, and Practice by George Simmons, Steven Krantz. McGraw-Hill NY. 2007. 1st Edition.
Section: Chapter 4. Power Series Solutions and Special Functions. Section 4.3. Second-Order Linear Equations: Ordinary Points. Page 169
Problem number: 1(b).
ODE order: 2.
ODE degree: 1.

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

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

Solution by Maple

Time used: 0.002 (sec). Leaf size: 69

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

\[ y \relax (x ) = \left (1-\frac {1}{6} x^{3}-\frac {1}{24} x^{4}-\frac {1}{120} x^{5}+\frac {1}{240} x^{6}+\frac {1}{630} x^{7}\right ) y \relax (0)+\left (x +\frac {1}{2} x^{2}+\frac {1}{6} x^{3}-\frac {1}{24} x^{4}-\frac {1}{30} x^{5}-\frac {1}{90} x^{6}-\frac {1}{1680} x^{7}\right ) D\relax (y )\relax (0)+O\left (x^{8}\right ) \]

Solution by Mathematica

Time used: 0.001 (sec). Leaf size: 91

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

\[ y(x)\to c_1 \left (\frac {x^7}{630}+\frac {x^6}{240}-\frac {x^5}{120}-\frac {x^4}{24}-\frac {x^3}{6}+1\right )+c_2 \left (-\frac {x^7}{1680}-\frac {x^6}{90}-\frac {x^5}{30}-\frac {x^4}{24}+\frac {x^3}{6}+\frac {x^2}{2}+x\right ) \]