Q87.The number of symmetric relations defined on the set {1, 2, 3, 4} which are not reflexive is _______.
What This Question Tests
This question tests the combinatorial counting of relations, specifically the number of symmetric relations that are not reflexive on a finite set. It requires understanding the definitions of these relation types.
Concepts Tested
Formulas Used
Number of relations = 2^(n*n)
Number of reflexive relations = 2^(n*(n-1))
Number of symmetric relations = 2^(n*(n+1)/2)
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📋 Question Details
- Chapter
- Sets Relations Functions
- Topic
- Types of Relations
- Year
- 2024
- Shift
- 30 Jan Shift 2
- Q Number
- Q87
- Type
- Numerical
- NCERT Ref
- Class 12 Mathematics Ch 1: Relations and Functions
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