हिंदी

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}

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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}

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

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एनसीईआरटी Mathematics Part 1 and 2 [English] Class 12
अध्याय 1 Relations and Functions
EXERCISE 1.1 | Q 1. (v). (b) | पृष्ठ ५
आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
अध्याय 1 Relations
Exercise 1.1 | Q 1.2 | पृष्ठ १०

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