Maximization by using derivatives
Given a function f(x), we can find the values of x that make f a maximum or a minimum by using derivatives.
Let f'(x) be the first derivative of f(x) and f''(x) the second derivative of f(x)
If f'(a) = 0 and f''(a) is negative, then x=a is a maximum
We'll use that criteria to find the maximum volume of the conical tank, restricted by the condition that the sum of radius and the height is 60 inches
