F prime is negative when x is greater than three. Well, that's exactly what I wrote up here. If f prime is negative, then that means that our slope of the tangent line of our original function f is going to be downward sloping, or that our function is decreasing. So this one is looking good. And this one right over here says f prime of zero is equal to negative three. So they're just pointing out this point. This isn't even relative to the interval that we care about, or this isn't even relative when x is greater than three.