This would be a maximum point. This would be a minimum point right over here. And then in a minimum point, your slope is zero right over there, but right before it, your slope was negative, and it goes to being positive. But you actually have cases where your derivative, your first derivative is zero, but you don't have an extremum. So for example, you could have a point like this, where right over here, your slope or your derivative could be equal to zero, and so your first derivative would be equal to zero, but notice, your slope is positive, it hits zero, and then it goes back to being positive again. And so you can't make the conclusion just because your derivative is zero that it's definitely an extremum. You could say it's a critical point, and so step two is correct.