Originally Posted by

**theowne** Let's say there's a question on maximizing volume of a box. So I write the constraint, plug it into the function, find the derivative, find when it's zero, sub it back in to the original function to find the volume, and I'm done. But how do I "test for max/min?". This is something that my teacher wrote over all of my answers "test for Max/min" on one and "test/check min" on the other....Do you think that just mean substituting into the derivative to make sure it's zero? Or making sure of the nature of the extrema to make sure its a maximum and no a minimum? Or is does it mean something I'm not familiar with?