Give an example of a relation which is symmetric but neither reflexive nor transitive.

Explanation

Let `A=\{5,6,7\}`.



Define a relation `R` on `A` as `R=\{(5,6),(6,5)\}`.



Relation `R` is not reflexive as `(5,5),(6,6),(7,7) \notin R`.



Now, as `(5,6) \in R` and also `(6,5) \in R, R` is symmetric.



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