Question

A={1, 2, 3, 4, …, 14}. Let R be a relation from A to A defined by
R = {(a, b):3a – b = 0, a, b∈ A} then domain of R is

• A. {3, 6, 9, 12}
• B. {1, 2, 3, 4}
• C. {1, 2, 3}
• D. {3, 6, 9}

Answer 1

The correct option is B

{1, 2, 3, 4}

Here (a, b) ∈ R, 3a = b,

Therefore

R = {(1, 3), (2, 6), (3, 9), (4, 12)}

Domain of relation R is the set of I elements of the ordered pairs
Domain R= {1, 2, 3, 4}