Q. 114.9( 10 Votes )

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

Answer :

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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