मराठी

Show that the relation R in R defined as R = {(a, b) : a ≤ b}, is reflexive and transitive but not symmetric.

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प्रश्न

Show that the relation R in R defined as R = {(a, b) : a ≤ b}, is reflexive and transitive but not symmetric.

बेरीज
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उत्तर

(i) Reflexive:

R = {(a, b) : a ≤ b}

Clearly, (a, a) ∈ R as a = a.

∴ R is reflexive.

(ii) Symmetric:

Now, (2, 4) ∈ R, as 2 < 4.

But (4, 2) ∉ R, as 4 is greater than 2.

∴ R is not symmetric.

(iii) Transitive:

Now, let (a, b), (b, c) ∈ R.

Then, a ≤ b and b ≤ c

⇒ a ≤ c

⇒ (a, c) ∈ R

∴ R is transitive.

Hence, R is reflexive and transitive but not symmetric.

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

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एनसीईआरटी Mathematics Part 1 and 2 [English] Class 12
पाठ 1 Relations and Functions
EXERCISE 1.1 | Q 4. | पृष्ठ ५

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