JEE Mains · Maths · STD 12 - 1. relation and function
The number of symmetric relations defined on the set \(\{1,2,3,4\}\) which are not reflexive is
- A \(950\)
- B \(940\)
- C \(960\)
- D \(965\)
Answer & Solution
Correct Answer
(C) \(960\)
Step-by-step Solution
Detailed explanation
Total number of relation both symmetric and reflexive \(=2^{\frac{\mathrm{n}^2-\mathrm{n}}{2}}\) Total number of symmetric relation \(=2^{\left(\frac{\mathrm{n}^2+\mathrm{n}}{2}\right)}\) \(\Rightarrow\) Then number of symmetric relation which are not reflexive \( \Rightarrow \)…
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