Answer: The missing ordered pairs are (2, 2), (2, 4), (2, 6), (3, 3) and (3, 6).
Step-by-step explanation: We are given the following set :
T = {1, 2, 3, 4, 5, 6}.
And, R = {(a, b) | a divides b} be a relation on the set T.
We are to identify the missing pairs from the following list of all ordered pairs in the given relation R on the set T :
{(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6), _____, (4, 4), (5, 5), and (6, 6).}.
Since R contains the ordered pairs (a, b) such that a divides b, so all the ordered pairs in R are
(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6), (2, 2), (2, 4), (2, 6), (3, 3), (3, 6), (4, 4), (5, 5), and (6, 6).
Thus, the missing ordered pairs are (2, 2), (2, 4), (2, 6), (3, 3) and (3, 6).
is just 
so it is just 2