Sey - when you say that you are unsure how to write it given that I have constants instead of number values, do you mean the variables (input parameters) to your function are what is causing the problem? And if so, why? From your description, the function signature would be
function [root] = secant(fun,a,b,epsilon)
How would you implement the secant method given its description found at http://en.wikipedia.org/wiki/Secant_method?
