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If R is a symmetric relation on a set A ...

If `R` is a symmetric relation on a set `A` , then write a relation between `R` and `R^(-1)` .

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To solve the problem, we need to establish the relationship between a symmetric relation \( R \) on a set \( A \) and its inverse \( R^{-1} \). ### Step-by-Step Solution: 1. **Definition of Symmetric Relation**: A relation \( R \) is symmetric if for every pair \( (a, b) \in R \), it also holds that \( (b, a) \in R \). 2. **Assume \( (a, b) \in R \)**: Let’s assume that \( (a, b) \) is an arbitrary element of the relation \( R \). 3. **Using the Definition of Symmetry**: Since \( R \) is symmetric, if \( (a, b) \in R \), then it must also be true that \( (b, a) \in R \). 4. **Definition of Inverse Relation**: The inverse of a relation \( R \), denoted \( R^{-1} \), consists of all pairs \( (b, a) \) such that \( (a, b) \in R \). Therefore, if \( (a, b) \in R \), then \( (b, a) \in R^{-1} \). 5. **Conclusion from the Above Steps**: Since \( (a, b) \in R \) implies \( (b, a) \in R \) (due to symmetry), and \( (b, a) \in R^{-1} \), we can conclude that \( R \subseteq R^{-1} \). 6. **Assume \( (x, y) \in R^{-1} \)**: Now, let’s take an arbitrary element \( (x, y) \in R^{-1} \). By the definition of the inverse relation, this means that \( (y, x) \in R \). 7. **Using the Symmetry of \( R \)**: Since \( R \) is symmetric, \( (y, x) \in R \) implies that \( (x, y) \in R \). 8. **Conclusion from the Above Steps**: Therefore, we can conclude that \( R^{-1} \subseteq R \). 9. **Final Conclusion**: Since we have shown that \( R \subseteq R^{-1} \) and \( R^{-1} \subseteq R \), we can conclude that \( R = R^{-1} \). ### Final Relation: Thus, the relation between \( R \) and \( R^{-1} \) is: \[ R = R^{-1} \]

To solve the problem, we need to establish the relationship between a symmetric relation \( R \) on a set \( A \) and its inverse \( R^{-1} \). ### Step-by-Step Solution: 1. **Definition of Symmetric Relation**: A relation \( R \) is symmetric if for every pair \( (a, b) \in R \), it also holds that \( (b, a) \in R \). 2. **Assume \( (a, b) \in R \)**: ...
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Knowledge Check

  • If R and S are two symmetric relations (not disjoint) on a set A, then the relation R cap S is

    A
    reflexive
    B
    symmetric
    C
    transitive
    D
    None of these
  • Let R be a relation from a set A to set B, then

    A
    `R=AuuB`
    B
    `R=AnnB`
    C
    `RsubeAxxB`
    D
    `RsupeBxxA`
  • Statement-1: If R is an equivalence relation on a set A, then R^(-1) is also an equivalence relation. Statement-2: R = R^(-1) iff R is a symmetric relation.

    A
    Statement-1 is True, Statement-2 is true, Statement-2 is a correct explanation for statement-1.
    B
    Statement-1 is True, Statement-2 is true, Statement-2 is not a correct explanation for Statement-1.
    C
    Statement-1 is True, Statement-2 is False
    D
    Statement-1 is False, Statement-2 is True.
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