And this term right over here, if we just look at it algebraically, would also be equal to zero, so this whole thing would be equal to zero. So someplace in between x equals zero and x equals 10, we should achieve our maximum volume. And before we do it analytically with a bit of calculus, let's do it graphically. So I'll get my handy TI-85 out. First let me set my range appropriately before I attempt to graph it. So I'll put my graph function. Let me set my range.