In mathematics, c stands for a complex set. It is often used as a symbolic expression of text description ellipsis in mathematical calculation and other occasions.

Set, for short, is a basic concept in mathematics and the main research object of set theory. The basic theory of set theory was founded in19th century. The simplest statement about set is the definition in naive set theory (the most primitive set theory), that is, set is "a certain pile of things" and the "things" in set are called elements. A modern set is usually defined as a whole consisting of one or more definite elements.

Extended data:

A collection of other letters

1, N* or N+: positive integer set {1, 2,3, ...}

2, z: integer set {…,-1, 0, 1, …}

3. Q: Rational number set

4.Q+: Positive Rational Number Set

5.Q-: set of negative rational numbers

6.r: set of real numbers (including rational numbers and irrational numbers)

7.R+: positive real number set

8.R-: negative real number set

Second, the operation law.

Exchange law: a ∩ b = b ∩ a; A∪B=B∪A

Law of constraint: a ∪ (b ∪ c) = (a ∪ b) ∪ c; A∩(B∩C)=(A∩B)∩C

The law of distribution duality: a ∩ (b ∪ c) = (a ∪ b) ∩ (a ∪ c); A ∪( B∪C)=(A∪B)∪( A∪C)

Duality law: (a ∪ b) c = a c ∪ b c; (A∩B)^C=A^C∪B^C

Identity: A∨? = A； A∩U=A

Baidu Encyclopedia -C (Mathematical Symbol)

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