Let A = {1, 2, 3, 4} and R = {(a, b): a A, b A, a divides b}. Write R explicitly.

given: A = {1, 2, 3, 4} and R = {(a, b): a A, b A, a divides b}

To find: set R


Both elements of R, a and b, belongs to set A and relation between and elements a and b is that a divides b


So,


1 divides 1, 2, 3 and 4.


2 divides 2 and 4.


3 divides 3.


4 divides 4.


R = {(1, 1), (1, 2), (1, 3), (1, 4), (2, 2), (2, 4), (3, 3), (4, 4)}


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