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The following defines a relation on N:x + 4y = 10 x, y ∈ N.Determine which of the above relations are reflexive, symmetric and transitive.

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Question

The following defines a relation on N:
x + 4y = 10 x, y ∈ N.
Determine which of the above relations are reflexive, symmetric and transitive.

Sum
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Solution

x + 4y = 10; x, y ∈ N

R = {(x, y): x + 4y = 10; x, y ∈ N}

R = {(2, 2), (6, 1)}

It’s clearly seen (1, 1) ∉ R

Hence, R is not symmetric.

(x, y) ∈ R ⇒ x + 4y = 10

And (y, z) ∈ R ⇒ y + 4z = 10

⇒ x – 16z = – 30

⇒ (x, z) ∉ R

Therefore, R is not transitive.

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Chapter 1: Relations And Functions - Exercise [Page 12]

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NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 1 Relations And Functions
Exercise | Q 22. (iv) | Page 12

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