# Math Help - Showing a kernel is valid

1. ## Showing a kernel is valid

Hi,
I'm trying to show that the kernel K(x, t) = 1/(1-xt) is a a valid kernel.

I guess I need to show that it reduces to an inner product somehow, but I cant quite see how.

Thanks

2. Originally Posted by Mathsdog
Hi, I'm trying to show that the kernel K(x, t) = 1/(1-xt) is a a valid kernel.

It is rather difficult to understand the "spirit" of the statement. For example, where the function $K$ is defined? . On what algebraic structures are we working?. Could you provide more details/hypothesis?.