Hence, the radius of the cylinder of greatest curved surface area
which can be inscribed in a given cone is half of that of the cone 6 4 1  Maximum and Minimum Values of a Function in a Closed Interval
Let us consider a function  f  given by
f (x) = x + 2, x ∈ (0, 1)
Observe that the function is continuous on (0, 1) and neither has a maximum value
nor has a minimum value