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Given an Example of a Relation. Which Is Transitive but Neither Reflexive Nor Symmetric. - Mathematics

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प्रश्न

Given an example of a relation. Which is Transitive but neither reflexive nor symmetric.

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उत्तर

Consider a relation R in defined as:

R = {(ab): a < b}

For any ∈ R, we have (aa) ∉ R since a cannot be strictly less than a itself. In fact, a = a.

∴ R is not reflexive.

Now,

(1, 2) ∈ R (as 1 < 2)

But, 2 is not less than 1.

∴ (2, 1) ∉ R

∴ R is not symmetric.

Now, let (ab), (bc) ∈ R.

⇒ a < b and b < c

⇒ a < c

⇒ (ac) ∈ R

∴R is transitive.

Hence, relation R is transitive but not reflexive and symmetric.

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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 10.2 | पृष्ठ ६

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