14.13 problem 13

Internal problem ID [1805]
Internal file name [OUTPUT/1806_Sunday_June_05_2022_02_32_53_AM_15775445/index.tex]

Book: Differential equations and their applications, 3rd ed., M. Braun
Section: Section 2.8.2, Regular singular points, the method of Frobenius. Page 214
Problem number: 13.
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.

\[ \boxed {t^{3} y^{\prime \prime }-t y^{\prime }-\left (t^{2}+\frac {5}{4}\right ) y=0} \] With the expansion point for the power series method at \(t = 0\).

The type of the expansion point is first determined. This is done on the homogeneous part of the ODE. \[ t^{3} y^{\prime \prime }-t y^{\prime }+\left (-t^{2}-\frac {5}{4}\right ) y = 0 \] The following is summary of singularities for the above ode. Writing the ode as \begin {align*} y^{\prime \prime }+p(t) y^{\prime } + q(t) y &=0 \end {align*}

Where \begin {align*} p(t) &= -\frac {1}{t^{2}}\\ q(t) &= -\frac {4 t^{2}+5}{4 t^{3}}\\ \end {align*}

Table 137: Table \(p(t),q(t)\) singularites.
\(p(t)=-\frac {1}{t^{2}}\)
singularity type
\(t = 0\) \(\text {``irregular''}\)
\(q(t)=-\frac {4 t^{2}+5}{4 t^{3}}\)
singularity type
\(t = 0\) \(\text {``irregular''}\)

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

Regular singular points : \([]\)

Irregular singular points : \([0, \infty ]\)

Since \(t = 0\) is not an ordinary point, then we will now check if it is a regular singular point. Unable to solve since \(t = 0\) 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 
   -> Kummer 
      -> 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 differential order: 2; exact nonlinear 
   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 
      -> Kummer 
         -> 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(t^3*diff(y(t),t$2)-t*diff(y(t),t)-(t^2+5/4)*y(t)=0,y(t),type='series',t=0);
 

\[ \text {No solution found} \]

Solution by Mathematica

Time used: 0.038 (sec). Leaf size: 97

AsymptoticDSolveValue[t^3*y''[t]-t*y'[t]-(t^2+5/4)*y[t]==0,y[t],{t,0,5}]
 

\[ y(t)\to c_2 e^{-1/t} \left (-\frac {239684276027 t^5}{8388608}+\frac {1648577803 t^4}{524288}-\frac {3127415 t^3}{8192}+\frac {26113 t^2}{512}-\frac {117 t}{16}+1\right ) t^{13/4}+\frac {c_1 \left (-\frac {784957 t^5}{8388608}-\frac {152693 t^4}{524288}-\frac {7649 t^3}{8192}-\frac {31 t^2}{512}+\frac {45 t}{16}+1\right )}{t^{5/4}} \]