How many relations are there on a set with 3 elements?
Answer and explanation
Correct answer: B. 2^9
- Step 1: A relation is a subset of A × A, which has 9 elements. Step 2. So there are 2^9 relations. Answer: 2^9. Why not the others: 2^3 is what you get if you use 2^n. 3^2 is what you get if you use n². 2^6 is what you get if you count only reflexive relations.
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