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The Question & Answer (Q&A) Knowledge Managenet

The Internet has many places to ask questions about anything imaginable and find past answers on almost everything.

Table of Contents

- What is the invention of John von Neumann?
- Who invented the Edvac?
- Who created set theory?
- What is a ∆ B?
- What does ø mean in math?
- What does U mean in math?
- What does AU mean in maths?
- What is C in set theory?
- What does U mean in discrete math?
- What is the U and upside down U in math?
- What is S in set theory?
- What is AB in set theory?
- What is a relation in set theory?

Interior-point methodVon Neumann entropy

J. Presper Eckert

Georg Cantor

A ∆ B = (A U B) – (A ∩ B) It implies that A ∆ B represents a set that contains the elements from the union of two sets, A and B, minus the intersection between them. Symmetric Difference, in other words, is also called disjunctive union. The symbol ∆ is also a binary operator.

empty set

Union

Astronomical Unit

In set theory, the complement of a set A, often denoted by Ac (or A′), are the elements not in A. When all sets under consideration are considered to be subsets of a given set U, the absolute complement of A is the set of elements in U that are not in A.

Special sets: – The universal set is denoted by U: the set of all objects under the consideration. Definition: A set A is said to be a subset of B if and only if every element of A is also an element of B.

These are used in set notation. U stands for union. And upside down U stands for intersection.. .For example given the set A = {1, 2, 3} and B = {3, 4, 5} Then A U B = {1, 2, 3, 4, 5} and A intersection B = { 3 }

S is an axiomatic set theory set out by George Boolos in his 1989 article, “Iteration Again”. S, a first-order theory, is two-sorted because its ontology includes “stages” as well as sets. Boolos designed S to embody his understanding of the “iterative conception of set“ and the associated iterative hierarchy.

The difference of set B from set A, denoted by A-B, is the set of all the elements of set A that are not in set B. In mathematical term, A-B = { x: x∈A and x∉B} If (A∩B) is the intersection between two sets A and B then, A-B = A – (A∩B)

A relation between two sets is a collection of ordered pairs containing one object from each set. If the object x is from the first set and the object y is from the second set, then the objects are said to be related if the ordered pair (x,y) is in the relation.