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+10 votes

The number of binary relations on a set with $n$ elements is:

  1. $n^2$

  2. $2^n$

  3. $2^{n^2}$

  4. None of the above


asked in Set Theory & Algebra by Veteran (69k points)
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1 Answer

+13 votes
Best answer
Answer: C

In a binary relation two elements are chosen from the set. So, with $n$ elements $n^2$ pairings are possible. Now, a relation can be any subset of these $n^2$ pairings and thus we get $2^{n^2}$ binary relations.
answered by Veteran (36.4k points)
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