So h prime of 9 is the same thing as 3 times f prime of 9 plus 2 times g prime of 9. Now what is f prime of 9, the derivative of our function f when x is equal to 9? Well, they tell us when x is equal to 9, f of 9 is 1. But more importantly, f prime of 9 is 3. So this part right over here evaluates that part's 3. But what's g prime of 9? So let's look at this function a little bit more closely.