Answer:
Armstrong's Axioms:
1.- Axiom of reflexivity
2.- Axiom of augmentation
3.- Axiom of transitivity
From these three axioms, the following are derived:
- Proyectivity or union
- Additivity or decomposition
- Pseudotransitivity
Explanation:
Be X, Y, W, Z are sets, then
1.- Axiom of reflexivity : ∀ Y ⊆ X ⇒ X → Y
2.- Axiom of augmentation : X →Y ⇒ ZX → ZY
3.- Axiom of transitivity: X → Y and Y → Z ⇒ X → Z
- Proyectivity or union: X → Y and X → Z ⇒ X → YZ
- Additivity or decomposition: X → Y and Z ⊆ Y ⇒ X → Z
- Pseudotransitivity: X → Y and WY → Z ⇒ WX → Z
