Materialy edukacyjne od Krzysztofa
Informatyka
Strona główna
Najlepsza algebraiczba zabawa - czyli algebra Boole'a
Popstulaty
Logika bramek
Postulaty
Postulaty Huntingtona
Elementy identycznościowe:
(X V 0 = X - odpowiednik bramki OR)
X + 0 = 0 + X = X (co oznacza, że:)
0 + 0 = 0 + 0 = 0
1 + 0 = 0 + 1 = 1
(X ⋀ 1 = X - odpowiednik bramki AND)
X * 1 = 1 * X = X (co oznacza, że:)
0 * 1 = 1 * 0 = 0
1 * 1 = 1 * 1 = 1
Alternatywa i koniunkcja (przemienność dodawania i mnożenia)
(X + Y = Y + X) :==: OR
0 + 0 = 0 + 0 = 0
0 + 1 = 1 + 0 = 1
1 + 1 = 1 + 1 = 1
(X * Y = Y * X) :==: AND
0 * 0 = 0 * 0 = 0
0 * 1 = 1 * 0 = 0
1 * 1 = 1 * 1 = 1
Łączność (asocjacja)
(X + Y) + Z = X + (Y + Z)
(0 + 0) + 0 = 0 + (0 + 0) = 0
(0 + 0) + 1 = 0 + (0 + 1) = 1
(0 + 1) + 0 = 0 + (1 + 0) = 1
(0 + 1) + 1 = 0 + (1 + 1) = 1
(1 + 0) + 0 = 1 + (0 + 0) = 1
(1 + 0) + 1 = 1 + (0 + 1) = 1
(1 + 1) + 0 = 1 + (1 + 0) = 1
(1 + 1) + 1 = 1 + (1 + 1) = 1
(X * Y) * Z = X * (Y * Z)
(0 * 0) * 0 = 0 * (0 * 0) = 0
(0 * 0) * 1 = 0 * (0 * 1) = 0
(0 * 1) * 0 = 0 * (1 * 0) = 0
(0 * 1) * 1 = 0 * (1 * 1) = 0
(1 * 0) * 0 = 1 * (0 * 0) = 0
(1 * 0) * 1 = 1 * (0 * 1) = 0
(1 * 1) * 0 = 1 * (1 * 0) = 0
(1 * 1) * 1 = 1 * (1 * 1) = 1
Absorpcja (∨ == + oraz ∧ == *)
X ∨ (X ∧ Y) = X ∧ (X ∨ Y) = X
inny zapis:
X + (X * Y) = X * (X + Y) = X
0 + (0 * 0) = 0 * (0 + 0) = 0
0 + (0 * 1) = 0 * (0 + 1) = 1
1 + (1 * 0) = 1 * (1 + 0) = 1
1 + (1 * 1) = 1 * (1 + 1) = 1
Dopełnienie
X ∨ ¬X = 1 (X + ¬X = 1 )
oraz
X ∧ ¬X = 0 (X * ¬X = 0)
1 + 0 = 1
1 * 0 = 0
Rozdzielniość operatorów
a ∨ (b ∧ c) = (a ∨ b) ∧ (a ∨ c) oraz a ∧ (b ∨ c) = (a ∧ b) ∨ (a ∧ c)
inny zapis:
a + (b * c) = (a + b) * (a + c) oraz a * (b + c) = (a * b) + (a * c)
Przykład:
0 + (0 * 0) = (0 + 0) * (0 + 0) = 0
1 + (0 * 0) = (1+ 0) * (1 + 0) = 1
itd.