MCQ
Let $A=\{3,5\}$. Then number of reflexive relations on $A$ is
  • A
    2
  • B
    4
  • C
    $0$
  • D
    8

Answer

Total number of reflexive relations on a set having $n$ number of elements $=2^{n^2-n}$
Here, $n=2$
$\therefore \quad$ Required number of reflexive relations $=2^{2^2-2}$ $=2^{4-2}=2^2=4$

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