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Given an example of a relation. Which is symmetric and transitive but not reflexive.

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प्रश्न

Given an example of a relation. Which is symmetric and transitive but not reflexive.

योग
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उत्तर

Let A = {1, 2}.

Define a relation R on A as:

R = {(1, 1)}

R is symmetric, because if (1, 1) ∈ R, then (1, 1) ∈ R.

R is transitive, because (1, 1) and (1, 1) imply (1, 1) ∈ R.

R is not reflexive, because (2, 2) ∉ R.

Hence, R is symmetric and transitive but not reflexive.

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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 10. (v) | पृष्ठ ६

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