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

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प्रश्न

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

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उत्तर

Let a relation R be defined on a set R.

R = {(a, b) : a3 ≥ b3}

Therefore, (a, a) ∈ R  ......[because a3 = a3]

∴ R is Reflexive.  ..... [because 23 ≥ 13]

Here, (2, 1) ∈ R  .....[because 13 ≥ 23]

∴ R is not symmetric.

Now, let (a, b) and (b, c) ∈ R.

∴ R is transitive.

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

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अध्याय 1: Relations - Exercise 1.1 [पृष्ठ ११]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 1 Relations
Exercise 1.1 | Q 14.2 | पृष्ठ ११

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