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Show that the relation R in the set {1, 2, 3} given by R = {(1, 2), (2, 1)} is symmetric but neither reflexive nor transitive. - Mathematics

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प्रश्न

Show that the relation R in the set {1, 2, 3} given by R = {(1, 2), (2, 1)} is symmetric but neither reflexive nor transitive.

योग
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उत्तर

(i) Reflexive:

Let A = {1, 2, 3}

A relation R on A is defined as R = {(1, 2), (2, 1)}

It is seen that (1, 1), (2, 2), and (3, 3) ∉ R.

∴ R is not reflexive.

(ii) Symmetric:

Now, as (1, 2) ∈ R and (2, 1) ∈ R. 

 ∴ R is symmetric.

(iii) Transitive:

Now, (1, 2) and (2, 1) ∈ R

However, (1, 1) ∉ R

∴ R is not transitive.

Hence, R is symmetric but neither reflexive nor transitive.

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अध्याय 1: Relations and Functions - Exercise 1.1 [पृष्ठ ६]

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एनसीईआरटी Mathematics Part 1 and 2 [English] Class 12
अध्याय 1 Relations and Functions
Exercise 1.1 | Q 6 | पृष्ठ ६

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