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Defines a Relation on N : X > Y, X, Y ∈ N Determine Which of the Above Relations Are Reflexive, Symmetric and Transitive.

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Question

Defines a relation on N :
  x > y, x, y ∈  N

Determine the above relation is reflexive, symmetric and transitive.

Sum
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Solution

We have,

R = {(x, y) : x > y, x, y ∈ N}

As, x = x ∀x ∈ N

⇒ (x,x) ∉ R

So, R is not a reflexive relation

Let (x,y) ∈ R

⇒ x > y

but  y < x

⇒ (y,x) ∉ R

So, R is not a symmeteric relation

Let (x,y)∈R and (y,z) ∈ R

⇒ x > y and y > z

⇒ x > z

⇒ (x,z) ∈ R

So, R is a transitive relation

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Chapter 1: Relations - Exercise 1.1 [Page 11]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 1 Relations
Exercise 1.1 | Q 18.1 | Page 11

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