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Show that the Relation '≥' on the Set R of All Real Numbers is Reflexive and Transitive but Not Symmetric. - Mathematics

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Question

Show that the relation '≥' on the set R of all real numbers is reflexive and transitive but not symmetric ?

Sum

Solution

 Let R be the set such that R = {(a, b) : ab ∈ Ra ≥ b}

Reflexivity :

Let a be an arbitrary element of R. 

⇒ a∈ R

⇒ a

⇒ ≥ a is true for a

⇒ (a, a∈ R

Hence, R is reflexive.

Symmetry :

Let (a, b∈ R

⇒ b is same as ≤ a, but not ≥ a

Thus, (b, a∉ R 

Hence, R is not symmetric .

Transitivity :

Let (a, b) and (b, c∈ R

≥ b and ≥ c

⇒ ≥ ≥ c

⇒ ≥ c

⇒ a, c∈ R

Hence, R is transitive .

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Chapter 1: Relations - Exercise 1.1 [Page 11]

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RD Sharma Mathematics [English] Class 12
Chapter 1 Relations
Exercise 1.1 | Q 13 | Page 11

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