How can I take the m'th solution from a infinite array of solutions?

greetings everyone,

from the following equation:

J(-1+n, x) = J(1+n, x)

(J(n,x) represents the first order bessel function)

I need to take the m'th solution. if someone could please help me with making a proper code for this problem, it would be very much appreciated. :)

kind regards, Nick Brum

Answer 1

[Star Strider]

If by ‘solution’ you mean ‘zero’, I suggest:

n = 2;
Jfcns = @(x) besselj(n-1, x) - besselj(n+1, x);

for k1 = 1:50
    Jzro(k1) = fzero(Jfcns,k1);
end
Jzro = unique(round(Jzro*1E4))/1E4;

% Get the 5th zero: 
Jz = Jzro(5);

x = linspace(0,max(Jzro), 500);

figure(1)
plot(x, Jfcns(x), '-b')
hold on
plot(Jzro, zeros(size(Jzro)), '+r', 'LineWidth', 1.5)
hold off
grid

Make the necessary changes to get the result you want.

[Star Strider]

My pleasure!

Answer 2

[Nick]

thank you very much for the reply! :)