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Question
Discuss the following relation for reflexivity, symmetricity and transitivity:
Let A be the set consisting of all the members of a family. The relation R defined by “aRb if a is not a sister of b”
Solution
A = {set of all members of the family}
aRb is a is not a sister of b
(a) aRa ⇒ a is not a sister of a It is reflexive
(b) aRb ⇒ a is not a sister of b.
bRa ⇒ b is not a sister of a.
It is symmetric
(c) aRb ⇒ a is not a sister of b.
bRc ⇒ b is not a sister of c.
aRc ⇒ a can be a sister of c
It is not transitive.
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