17.4 problem 5

Internal problem ID [2920]
Internal file name [OUTPUT/2412_Sunday_June_05_2022_03_06_58_AM_35030435/index.tex]

Book: Differential equations and linear algebra, Stephen W. Goode and Scott A Annin. Fourth edition, 2015
Section: Chapter 11, Series Solutions to Linear Differential Equations. Exercises for 11.4. page 758
Problem number: 5.
ODE order: 2.
ODE degree: 1.

The type(s) of ODE detected by this program : "second order series method. Irregular singular point"

Maple gives the following as the ode type

[[_2nd_order, _with_linear_symmetries]]

Unable to solve or complete the solution.

\[ \boxed {y^{\prime \prime }+\frac {2 y^{\prime }}{x \left (x -3\right )}-\frac {y}{x^{3} \left (x +3\right )}=0} \] With the expansion point for the power series method at \(x = 0\).

The type of the expansion point is first determined. This is done on the homogeneous part of the ODE. \[ y^{\prime \prime }+\frac {2 y^{\prime }}{x \left (x -3\right )}-\frac {y}{x^{3} \left (x +3\right )} = 0 \] The following is summary of singularities for the above ode. Writing the ode as \begin {align*} y^{\prime \prime }+p(x) y^{\prime } + q(x) y &=0 \end {align*}

Where \begin {align*} p(x) &= \frac {2}{x \left (x -3\right )}\\ q(x) &= -\frac {1}{x^{3} \left (x +3\right )}\\ \end {align*}

Table 172: Table \(p(x),q(x)\) singularites.
\(p(x)=\frac {2}{x \left (x -3\right )}\)
singularity type
\(x = 0\) \(\text {``regular''}\)
\(x = 3\) \(\text {``regular''}\)
\(q(x)=-\frac {1}{x^{3} \left (x +3\right )}\)
singularity type
\(x = -3\) \(\text {``regular''}\)
\(x = 0\) \(\text {``irregular''}\)

Combining everything together gives the following summary of singularities for the ode as

Regular singular points : \([3, -3, \infty ]\)

Irregular singular points : \([0]\)

Since \(x = 0\) is not an ordinary point, then we will now check if it is a regular singular point. Unable to solve since \(x = 0\) is not regular singular point. Terminating.

Verification of solutions N/A

Maple trace

`Methods for second order ODEs: 
--- Trying classification methods --- 
trying a quadrature 
checking if the LODE has constant coefficients 
checking if the LODE is of Euler type 
trying a symmetry of the form [xi=0, eta=F(x)] 
checking if the LODE is missing y 
-> Trying a Liouvillian solution using Kovacics algorithm 
<- No Liouvillian solutions exists 
-> Trying a solution in terms of special functions: 
   -> Bessel 
   -> elliptic 
   -> Legendre 
   -> Whittaker 
      -> hyper3: Equivalence to 1F1 under a power @ Moebius 
   -> hypergeometric 
      -> heuristic approach 
      -> hyper3: Equivalence to 2F1, 1F1 or 0F1 under a power @ Moebius 
   -> Mathieu 
      -> Equivalence to the rational form of Mathieu ODE under a power @ Moebius 
trying a solution in terms of MeijerG functions 
-> Heun: Equivalence to the GHE or one of its 4 confluent cases under a power @ Moebius 
-> trying a solution of the form r0(x) * Y + r1(x) * Y where Y = exp(int(r(x), dx)) * 2F1([a1, a2], [b1], f) 
   trying a symmetry of the form [xi=0, eta=F(x)] 
   trying 2nd order exact linear 
   trying symmetries linear in x and y(x) 
   trying to convert to a linear ODE with constant coefficients 
   trying 2nd order, integrating factor of the form mu(x,y) 
   -> Trying a solution in terms of special functions: 
      -> Bessel 
      -> elliptic 
      -> Legendre 
      -> Whittaker 
         -> hyper3: Equivalence to 1F1 under a power @ Moebius 
      -> hypergeometric 
         -> heuristic approach 
         -> hyper3: Equivalence to 2F1, 1F1 or 0F1 under a power @ Moebius 
      -> Mathieu 
         -> Equivalence to the rational form of Mathieu ODE under a power @ Moebius 
      trying 2nd order exact linear 
      trying symmetries linear in x and y(x) 
      trying to convert to a linear ODE with constant coefficients 
      trying to convert to an ODE of Bessel type 
   trying to convert to an ODE of Bessel type 
   -> trying reduction of order to Riccati 
      trying Riccati sub-methods: 
         -> trying a symmetry pattern of the form [F(x)*G(y), 0] 
         -> trying a symmetry pattern of the form [0, F(x)*G(y)] 
         -> trying a symmetry pattern of the form [F(x),G(x)*y+H(x)] 
--- Trying Lie symmetry methods, 2nd order --- 
`, `-> Computing symmetries using: way = 3`[0, y]
 

Solution by Maple

Order:=6; 
dsolve(diff(y(x),x$2)+2/(x*(x-3))*diff(y(x),x)-1/(x^3*(x+3))*y(x)=0,y(x),type='series',x=0);
 

\[ \text {No solution found} \]

Solution by Mathematica

Time used: 0.223 (sec). Leaf size: 258

AsymptoticDSolveValue[y''[x]+2/(x*(x-3))*y'[x]-1/(x^3*(x+3))*y[x]==0,y[x],{x,0,5}]
 

\[ y(x)\to c_1 e^{-\frac {2}{\sqrt {3} \sqrt {x}}} \left (\frac {10879996003390494539 x^{9/2}}{6059672463464202240 \sqrt {3}}+\frac {64713480610417 x^{7/2}}{328758271672320 \sqrt {3}}+\frac {287821451 x^{5/2}}{3397386240 \sqrt {3}}+\frac {19817 x^{3/2}}{73728 \sqrt {3}}-\frac {4894564486149401320457 x^5}{1246561192484064460800}-\frac {116612812982297797 x^4}{378729528966512640}-\frac {22160647459 x^3}{587068342272}+\frac {463507 x^2}{42467328}+\frac {587 x}{4608}+\frac {25 \sqrt {x}}{16 \sqrt {3}}+1\right ) x^{13/12}+c_2 e^{\frac {2}{\sqrt {3} \sqrt {x}}} \left (-\frac {10879996003390494539 x^{9/2}}{6059672463464202240 \sqrt {3}}-\frac {64713480610417 x^{7/2}}{328758271672320 \sqrt {3}}-\frac {287821451 x^{5/2}}{3397386240 \sqrt {3}}-\frac {19817 x^{3/2}}{73728 \sqrt {3}}-\frac {4894564486149401320457 x^5}{1246561192484064460800}-\frac {116612812982297797 x^4}{378729528966512640}-\frac {22160647459 x^3}{587068342272}+\frac {463507 x^2}{42467328}+\frac {587 x}{4608}-\frac {25 \sqrt {x}}{16 \sqrt {3}}+1\right ) x^{13/12} \]