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If R is a Symmetric Relation on a Set A, Then Write a Relation Between R and R−1.

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Question

If R is a symmetric relation on a set A, then write a relation between R and R−1.

Sum
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Solution

Here, R is symmetric on the set A.

Let (a, b) ∈ R

⇒ (b, a) ∈ R                  [Since R is symmetric]

⇒ (a, b) ∈ R−1               [By definition of inverse relation]

⇒ R ⊂ R−1

Let (x, y) ∈ R−1

⇒ (y, x) ∈ R                     [By definition of inverse relation]

⇒ (x, y) ∈ R                    [Since R is symmetric]

⇒ R−1 ⊂ R

Thus, R = R−1

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Chapter 1: Relations - Exercise 1.3 [Page 30]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 1 Relations
Exercise 1.3 | Q 6 | Page 30

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