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 live in the same locality} - Mathematics

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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 live in the same locality}

बेरीज
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उत्तर

(i) Reflexivity:

(x, x) ∈ R because x and x live in the same locality.

∴ R is reflexive.

(ii) Symmetry:

Let (x, y) ∈ R

⇒ x and y live in the same locality.

⇒ y and x also live in the same locality.

⇒ (y, x) ∈ R 

Thus, R is symmetric.

(iii) Transitivity:

Let (x, y) ∈ R and (y, z) ∈ R

⇒ x and y live in the same locality and y and z live in the same locality.

⇒ x and z live in the same locality .

⇒ (x, z) ∈ R

Thus, R is transitive.

Hence, R is reflexive, symmetric and transitive.

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पाठ 1: Relations - Exercise 1.1 [पृष्ठ १०]

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आरडी शर्मा Mathematics [English] Class 12
पाठ 1 Relations
Exercise 1.1 | Q 1.2 | पृष्ठ १०
एनसीईआरटी Mathematics Part 1 and 2 [English] Class 12
पाठ 1 Relations and Functions
Exercise 1.1 | Q 1. 5. (b) | पृष्ठ ५

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