मराठी

Check whether the relation R in R defined by R = {(a, b) : a ≤ b3} is reflexive, symmetric or transitive. - Mathematics

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प्रश्न

Check whether the relation R in R defined by R = {(a, b) : a ≤ b3} is reflexive, symmetric or transitive.

बेरीज
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उत्तर

(i) Reflexive:

Let a ∈ R, a ≤ a3, which is false.

∴ (a, a) ∉ R

Thus, R is not reflexive.

(ii) Symmetric:

Let a, b ∈ R, and (a, b) ∈ R

⇒ a ≤ b3

Does not imply b ≤ a3

(b, a) ∉ R

Thus, R is not symmetric.

(iii) Transitive:

Let a, b, c ∈ R; consider (a, b) ∈ R and (b, c) ∈ R

⇒ a ≤ band b ≤ c3

⇒ a ≤ c3 is false.

⇒ (a, c) ∉ R

∴ R is not transitive.

Hence, R is neither reflexive, nor symmetric, nor transitive.

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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 5 | पृष्ठ ५
आरडी शर्मा Mathematics [English] Class 12
पाठ 1 Relations
Exercise 1.1 | Q 7 | पृष्ठ ११

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