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Determine whether the following relation is reflexive, symmetric and transitive: Relation R in the set N of natural numbers defined as R = {(x, y) : y = x + 5 and x < 4}. - Mathematics

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प्रश्न

Determine whether the following relation is reflexive, symmetric and transitive:

Relation R in the set N of natural numbers defined as R = {(x, y) : y = x + 5 and x < 4}.

योग
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उत्तर

R = {(x, y) : y = x + 5 and x < 4} = {(1, 6), (2, 7), (3, 8)}

It is seen that (1, 1) ∉ R.

∴ R is not reflexive.

(1, 6) ∈ R but (1, 6) ∉ R.

∴ R is not symmetric.

Now, since there is no pair in R such that (x, y) and (y, z) ∈ R, we need to look for the ordered pair (x, y). 

∴ R is transitive.

Hence, R is neither reflexive, nor symmetric, but it is 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 1.2 | पृष्ठ ५

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