So to figure out critical points, we essentially have to find the derivative of our function and figure out when does that derivative equal zero or when is that derivative undefined? That's the definition of critical points. So p prime of x is going to be equal to negative 3x squared plus 12x minus five. And so this thing is going to be defined for all x. So the only critical points we're going to have is when the first derivative right over here is equal to zero. So negative 3x squared plus 12x minus five needs to be equal to zero in order for x to be a critical point. So now we just have to solve for x.