मराठी

Give an example of a relation which is symmetric and transitive but not reflexive?

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प्रश्न

Give an example of a relation which is symmetric and transitive but not reflexive?

बेरीज
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उत्तर

Let A = {−5, −6}

The relation R on a set A is defined as follows:

R = {−5, −6), (−6, −5), (−5, −5)}

The relation R is not reflexive because (−6, −6) ∉ R.

∴ R is not reflexive.

⇒ The relation R is symmetric because (−5, −6) ∈ R and (−6, −5) ∈ R.

∴ R is symmetric.

⇒ And, if (−5, −6) and (−6, −5) ∈ R, then (−5, −5) ∈ R

∴ R is transitive.

Hence, the relation R is symmetric and transitive but not reflexive.

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पाठ 1: Relations - Exercise 1.1 [पृष्ठ ११]

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आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
पाठ 1 Relations
Exercise 1.1 | Q 14.3 | पृष्ठ ११

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