Let g be the function g of x is equal to one over x. Let capital F be a function defined as the product of those other two functions. What is capital F prime of negative one? Well, we can just apply the product rule here. Let me just rewrite, let me just essentially state the product rule. Capital F prime of x is going to be equal to, since capital F of x is the product of these two functions, we apply the product rule, this is going to be f prime of x times g of x plus f of x times g prime of x. If we want to evaluate this at negative one, capital F prime at negative one is equal to f prime of negative one times g of negative one plus function f evaluated at negative one times the derivative of g evaluated at negative one.