Slide 16
Area Approximation
So the width of each rectangle is
The height of each rectangle is either
or
So the upper and lower sums can be defined as
Lower sum
Upper sum
Slide 17
Area Approximation
It is important to note that
Neither approximation will give you the actual area
Either approximation can be found to such a degree that it is accurate enough by taking the limit as n goes to infinity
In other words