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Sets and operations
Membership, subsets, union, intersection, complement, and Venn diagrams.
A set is a collection; the operations combine them: union (either), intersection (both), difference, complement. Picture it: a Venn diagram; each region is a combination of memberships. Think it: the operations satisfy the same laws as and/or/not, sets and logic are the same algebra (Boolean algebra).
Voorbeeld van werk · {1,2,3,4} union {3,4,5,6}
{1,2,3,4} union {3,4,5,6}
Stap voor stap
- A = \left\{1, 2, 3, 4\right\},\quad B = \left\{3, 4, 5, 6\right\}
The two sets.
- A \cup B = \left\{1, 2, 3, 4, 5, 6\right\}
Keep everything in either set.
- |A| = 4,\ |B| = 4,\ |A \cup B| = 6
Cardinalities. Note |A ∪ B| = |A| + |B| − |A ∩ B|.
Onthul het antwoord
Nu jij. Kies een probleem, type of teken je eigen. Elke stap, een foto, het antwoord verborgen totdat je het vraagt.
Hier gebruikte symbolen
Tik op elk symbool voor de volledige definitie, een afbeelding en wat elke letter erin betekent.
Hoe: Sets and operations
- Write each set explicitly, or describe it by a property.
- For a union keep everything in either; for an intersection only what is in both.
- Check |A ∪ B| = |A| + |B| − |A ∩ B|.
Vragen die mensen stellen
Are some infinities bigger than others?
Yes. The integers and the rationals can be listed; the real numbers cannot (Cantor's diagonal argument), so there are strictly more reals than integers.
What is the difference between a relation and a function?
A relation pairs inputs with outputs freely; a function is a relation in which every input gets exactly one output.
Meer in Set Theory & Logic
Relations, functions and equivalenceCardinality and infinityLogic and methods of proof