Lecture 16 : Integral from upper and lower sums [Section 16.1]
16.1.12
Example:
(i)
Let
We show that is an integrable function. For , consider
be a partition of obtained by dividing into equal parts, i.e.,
Then, is a sequence of refinement partitions and for all , we have
is an integrable function. For 
, consider 
obtained by dividing 
into 
equal parts, i.e., 
is a sequence of refinement partitions and for all 
, we have 
