Well, if the fact that we cross, that we're at the x-axis, that x equals, that y is equal to zero, that the function, that the derivative is equal to zero at x equals eight, that tells us that the slope of the tangent line of g at that point is zero, but that alone does not tell us we have a relative minimum point. In order to have a relative minimum point, our derivative has to cross from being negative to positive. Why is that valuable? Because think about, if your derivative goes from being negative to positive, that means your original function goes from decreasing to increasing, goes from decreasing to increasing, and so you would have a relative minimum point. And the choice that describes that, this is starting to get there, but this alone isn't enough for a relative minimum point. F is negative before x equals eight and positive after x equals eight. That's exactly what we just described.