Problem with Sturm-Liouville equation

  • Thread starter Thread starter Transcend
  • Start date Start date
Transcend
Messages
3
Reaction score
0
Hi there :smile: .
I'm having troubles at a point in one Sturm-Liouville problem .

I am trying to convert a generation eqn to the form of a Sturm-Liouville equation. The equation's form is as follows (where a(x),b(x),c(x),d(x) are arbitrary functions):

a(x)y'' + b(x)y'(x) + [c(x) + (LAMBDA)d(x)]y(x) = o

I begin by formatting in y'' + ... form. How do I proceed from here, please?

Ciao,

Transcend
 
Physics news on Phys.org
If b(x) = a'(x) your equation is in Sturm-Liouville form...
 
If not, then you need to multiply by some \mu(x) so that it is:
a(x)\mu(x)y'' + b(x)\mu(x)y'(x) + [c(x) + (\lambda(x))d(x)]\mu(x)y(x) = 0

With a'\mu(x)+ a\mu'(x)= b(x)\mu(x). That gives you a simple differential equation for \mu(x).
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
Back
Top