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

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प्रश्न

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

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उत्तर

Let A = {5, 6, 7}

⇒ And the relation R = {(5, 6), (6, 5)}

The relation R is not reflexive because (5, 5), (6, 6), and (7, 7) ∉ R.

∴ R is not reflexive.

⇒ Now, since (5, 6) ∈ R and (6, 5) ∈ R.

∴ R is symmetric.

⇒ (5, 6), (6, 5) ∈ R, but (5, 5) ∉ R

∴ R is not transitive. 

Hence, the relation R is symmetric but neither reflexive nor transitive.

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अध्याय 1: Relations - Exercise 1.1 [पृष्ठ ११]

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आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
अध्याय 1 Relations
Exercise 1.1 | Q 14.4 | पृष्ठ ११

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