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Show that the relation R in the set R of real numbers, defined as R = {(a, b): a ≤ b2} is neither reflexive nor symmetric nor transitive. - Mathematics

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प्रश्न

Show that the relation R in the set of real numbers, defined as R = {(a, b): a ≤ b2} is neither reflexive nor symmetric nor transitive.

योग

उत्तर

(i) Reflexive:

R = {(a, b): a ≤ b2}

Let a ∈ R 

a ≤ a2 which is false

(a, a) ∉ R

∴R is not reflexive.

(ii) Symmetric:

Let a, b ∈ R and (a, b) ∈ R

a ≤ b2 and b ≤ a2, which is false

(a, b) ∈ R, but (b, a) ∉ R

∴ R is not symmetric

(iii) Transitive:

Let a, b,c ∈ R

Consider (a, b) ∈ R, (b, c) ∈ R

a ≤ b2 and b ≤ c2

a≤ c2 is false

(a, c) ∉ R

∴ R is not transitive.

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

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अध्याय 1: Relations and Functions - Exercise 1.1 [पृष्ठ ५]

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एनसीईआरटी Mathematics [English] Class 12
अध्याय 1 Relations and Functions
Exercise 1.1 | Q 2 | पृष्ठ ५

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