4.11 problem 19

Internal problem ID [5899]

Book: DIFFERENTIAL EQUATIONS with Boundary Value Problems. DENNIS G. ZILL, WARREN S. WRIGHT, MICHAEL R. CULLEN. Brooks/Cole. Boston, MA. 2013. 8th edition.
Section: CHAPTER 6 SERIES SOLUTIONS OF LINEAR EQUATIONS. CHAPTER 6 IN REVIEW. Page 271
Problem number: 19.
ODE order: 2.
ODE degree: 1.

CAS Maple gives this as type [[_Emden, _Fowler]]

\[ \boxed {x y^{\prime \prime }+\left (1-\cos \left (x \right )\right ) y^{\prime }+x^{2} y=0} \] With the expansion point for the power series method at \(x = 0\).

Solution by Maple

Time used: 0.0 (sec). Leaf size: 59

Order:=8; 
dsolve(x*diff(y(x),x$2)+(1-cos(x))*diff(y(x),x)+x^2*y(x)=0,y(x),type='series',x=0);
 

\[ y \left (x \right ) = \left (1-\frac {1}{6} x^{3}+\frac {1}{80} x^{5}+\frac {1}{180} x^{6}-\frac {5}{4032} x^{7}\right ) y \left (0\right )+\left (x -\frac {1}{12} x^{3}-\frac {1}{12} x^{4}+\frac {1}{120} x^{5}+\frac {1}{120} x^{6}+\frac {73}{60480} x^{7}\right ) D\left (y \right )\left (0\right )+O\left (x^{8}\right ) \]

Solution by Mathematica

Time used: 0.002 (sec). Leaf size: 36

AsymptoticDSolveValue[x*y''[x]+(1-Cos[x])*y'[x]+x^2*y[x]==0,y[x],{x,0,7}]
 

\[ y(x)\to -\frac {53 x^7}{8640}+\frac {x^5}{48}+\frac {x^4}{6}-\frac {x^3}{3}-2 x+3 \]