मराठी

Let A be the set of all human beings in a town at a particular time. Determine whether the following relation is reflexive, symmetric and transitive: R = {(x, y) : x and y work at the same place}

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प्रश्न

Let A be the set of all human beings in a town at a particular time. Determine whether the following relation is reflexive, symmetric and transitive:

 R = {(x, y) : x and y work at the same place}

बेरीज
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उत्तर

(i) Reflexivity: 

Let x be an arbitrary element of R.

Then, x ∈ R   

⇒ x and x work at the same place,

Which is true since they are the same.

⇒ (x, x) ∈ R

∴ R is a reflexive relation.

(ii) Symmetry:

Let (x, y) ∈ R

⇒ x and y work at the same place.

⇒ y and x work at the same place.

⇒ (y, x) ∈ R

∴ R is a symmetric relation.

(iii) Transitivity:

Let (x, y) ∈ R and (y, z) ∈ R.

Then, x and y work at the same place.

y and z also work at the same place.

⇒ x, y and z all work at the same place.

⇒ x and z work at the same place.

⇒ (x, z) ∈ R

∴ R is a transitive relation.

Hence, R is reflexive, symmetric and transitive.

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पाठ 1: Relations and Functions - EXERCISE 1.1 [पृष्ठ ५]

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एनसीईआरटी Mathematics Part 1 and 2 [English] Class 12
पाठ 1 Relations and Functions
EXERCISE 1.1 | Q 1. (v). (a) | पृष्ठ ५
आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
पाठ 1 Relations
Exercise 1.1 | Q 1.1 | पृष्ठ १०

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