The domain of the following relation: r: {(3, 5), (8, 6), (2, 1), (8, 6)} is

{2, 3, 8}

Step-by-step explanation:

Domain is the of set all x-coordinates of the ordered pair in the relation.

As per the statement:

Given the relation:

R: ={(3, 5), (8, 6), (2, 1), (8, 6)}

Since, the ordered pair is in the form of (x, y)

x-coordinates are 3, 8, 2

y-coordinates are: 5, 6, 1

By definition of domain:

Domains of the following relation R is, {2, 3, 8}