- #1

- 40

- 0

(k(x)*g(x)')'=p*g(x)

where

k(x) = k(x+T) -- k(x) is a known periodical function of period T, k(x) real, x real, T real.

p = some constant that have to be determined.

g(x) = an unknown function.

**Question:**

*Is there a method that can tell from the beginning that all the values of p should be real?*

If p is always real I will try to solve the equation if p could also be complex the equation will not be of so much interest for me.