12.12.14 problem 16

Internal problem ID [1868]
Book : Elementary differential equations with boundary value problems. William F. Trench. Brooks/Cole 2001
Section : Chapter 7 Series Solutions of Linear Second Equations. 7.2 SERIES SOLUTIONS NEAR AN ORDINARY POINT I. Exercises 7.2. Page 329
Problem number : 16
Date solved : Monday, January 27, 2025 at 05:37:33 AM
CAS classification : [[_2nd_order, _missing_x]]

\begin{align*} y^{\prime \prime }-y&=0 \end{align*}

Using series method with expansion around

\begin{align*} 3 \end{align*}

✓ Solution by Maple

Time used: 0.002 (sec). Leaf size: 48

Order:=6; 
dsolve(diff(y(x),x$2)-y(x)=0,y(x),type='series',x=3);
 

\[ y = \left (1+\frac {\left (x -3\right )^{2}}{2}+\frac {\left (x -3\right )^{4}}{24}\right ) y \left (3\right )+\left (x -3+\frac {\left (x -3\right )^{3}}{6}+\frac {\left (x -3\right )^{5}}{120}\right ) y^{\prime }\left (3\right )+O\left (x^{6}\right ) \]

✓ Solution by Mathematica

Time used: 0.001 (sec). Leaf size: 51

AsymptoticDSolveValue[D[y[x],{x,2}]-y[x]==0,y[x],{x,3,"6"-1}]
 

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