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Question

Let R be the relation on the set of positive integers such that aRb if and only if a and b are distinct and have a common divisor other than 1. Which one of the following statements about R is True?

a.

R is symmetric and reflexive but not transitive

b.

R is reflexive but not symmetric and not transitive

c.

R is transitive but not reflexive and not symmetric

d.

R is symmetric but not reflexive and not transitive

Answer: (d).R is symmetric but not reflexive and not transitive

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Q. Let R be the relation on the set of positive integers such that aRb if and only if a and b are distinct and have a common divisor other than 1. Which one of the following...

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