How to prove “A->B,C then A->B and A->C” from Armstrong Axioms
문제
I know that this is true but I don't understand how to prove it.
The Problem:
Prove or disprove that if A->B,C, then A->B and A->C
This answer is similar but it does not prove the relation using Armstrong's axioms.
해결책
Just two steps: you can use reflexivity for B C -> B
and then transitivity from A -> B C
and the previous dependency. Analogous solution for the second case.
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