# Fredhoim Integral

For some parameter-distributed system/unlimited dimensional system, why is it possible to describe the relationship between input signal $$u(t)$$ and controlled signal $$y(t)$$ in the form of Fredhoim integral? $$y(x) = \int_{a}^{b}K(x,s)g(y(s),u(s))ds$$ where $$K(s)$$ is an known function of two variables (kernel of the integral),$$g(y,u)$$ is an known function function of two variables and $$u(s)$$is control input function.

• This question does not appear to be about the software application Mathematica or the Wolfram language. You have probably posted on the wrong StackExchange site. – Bob Hanlon Dec 3 at 2:08