Hi all. I'm using a model from a paper my supervisor forwarded me to for my Dissertation, however there's one part of it I'm failing to understand. As this is a basic problem, I decided to post it here.

It states that k_exci is an increasing function of v on the interval 0 <= v <= v_exci

It then goes on to give an input to k0_exci (where the 0 is superscript) = 5.

I'm not sure how I can get a function from this where its only value given is 5?