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How to solve Bessel function

  1. Oct 16, 2007 #1
    If we want to find x giving J_m(x)=0 where m=any constants, how can we analytically get x?

    Thank you
  2. jcsd
  3. Oct 16, 2007 #2


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    I don't think you can do that analytically. (from memory)
  4. Oct 16, 2007 #3
    I also use mathematica to solve but it doesn't help.
  5. Oct 16, 2007 #4


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    You'll have an infinite number of real roots.

    For large x, you can use the asymptotic formula for [tex]J_n(x)[/tex]. If I remember right, the difference between successive roots will tend to [itex]\pi[/itex] for large x.

    Alternatively, you could look up tables which give the zeros for various Bessel functions in a mathematical handbook
  6. Oct 16, 2007 #5
    There will be the analytic solution when we assume x -> infinity or x<<1. In the case of the first few values of x giving J_m(x)=0, we might have to use the table to be the last choice. Anyway, thanks mjsd and siddharth.
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