Converting 2nd order ODE to Bessel Function

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Homework Help Overview

The discussion revolves around converting a second-order ordinary differential equation (ODE) into a form that relates to Bessel functions. The original ODE presented is of the form \(xd^{2}y/dx^{2}-3dy/dx+xy=0\), and participants are exploring methods to manipulate this equation to identify its relationship with Bessel's equation.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to factor out \(x^{-1}\) from the ODE to simplify it, questioning the legality of this operation. Other participants suggest alternative manipulations, such as multiplying the equation by \(x\) instead. There is also a discussion about the implications of dividing by \(x\) in a different example, particularly concerning the behavior as \(x\) approaches zero.

Discussion Status

The discussion is active, with participants providing different perspectives on how to manipulate the original equation. Some guidance has been offered regarding the operations on the ODE, but there is no explicit consensus on the best approach to take. The original poster expresses uncertainty about how to proceed after transforming the equation into a specific form.

Contextual Notes

Participants are considering the implications of their manipulations, particularly regarding the behavior of the solutions near \(x = 0\). There is an acknowledgment of the need to be cautious when dividing by terms that could lead to undefined behavior.

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Homework Statement


I am attempting to solve the 2nd order ODE as follows using the generalized solution to the Bessel's equation


Homework Equations


original ODE:
x[tex]d^{2}y/dx^{2}[/tex]-3[tex]dy/dx[/tex]+xy=0

The Attempt at a Solution


My first thought is to bring out an x^-1 outside of the function so that I end up with:
[tex]x^{-1}([/tex][tex]x^{2}[/tex][tex]d^{2}y/dx^{2}[/tex]-3x[tex]dy/dx[/tex]+[tex]x^{2}[/tex]y)=0
I would then solve the resulting Bessel equation found inside the parentheses, and multiply the resulting solution by x^-1. Is this at all a legal operation? Thank you.
 
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There is no need for the x-1 outside. Just multiply both sides of the original equation by x.
 
Now if the opposite were true and I was trying to drop the power of x's by 1:

example: (x^3)[tex]d^{2}y[/tex]/[tex]dx^{2}[/tex]+(x^2)dy/dx+(x^3)y=0

Could I then instead divide by x to come up with:
(x^2)[tex]d^{2}y[/tex]/[tex]dx^{2}[/tex]+(x)dy/dx+(x^2)y=0

with the understanding that the solution to the resulting Bessel function would exclude any results for when x-> 0?
 
Well, because x2 still multiplying the second derivative that would be a problem any way, but you are right if you divided by something that completely got rid of a function multiplying the highest derivative, then you would have to add that condition.
 
Hey I need some help in converting the second order differential equation into..
I was able to convert the original equation into the following form x^2*y''+2x*y'+x^2*y=0
I am not able to move forward from here..
Please could you suggest some method
 

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