Glossary of mathematical symbols

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Template:Short description A mathematical symbol is a figure or a combination of figures that is used to represent a mathematical object, an action on mathematical objects, a relation between mathematical objects, or for structuring the other symbols that occur in a formula or a mathematical expression. More formally, a mathematical symbol is any grapheme used in mathematical formulas and expressions. As formulas and expressions are entirely constituted with symbols of various types, many symbols are needed for expressing all mathematics.

The most basic symbols are the decimal digits (0, 1, 2, 3, 4, 5, 6, 7, 8, 9), and the letters of the Latin alphabet. The decimal digits are used for representing numbers through the Hindu–Arabic numeral system. Historically, upper-case letters were used for representing points in geometry, and lower-case letters were used for variables and constants. Letters are used for representing many other types of mathematical object. As the number of these types has increased, the Greek alphabet and some Hebrew letters have also come to be used. For more symbols, other typefaces are also used, mainly boldface Template:Tmath, script typeface 𝒜,, (the lower-case script face is rarely used because of the possible confusion with the standard face), German fraktur Template:Tmath, and blackboard bold Template:Tmath (the other letters are rarely used in this face, or their use is unconventional). It is commonplace to use alphabets, fonts and typefaces to group symbols by type (for example, boldface is often used for vectors and uppercase for matrices).

The use of specific Latin and Greek letters as symbols for denoting mathematical objects is not described in this article. For such uses, see Variable § Conventional variable names and List of mathematical constants. However, some symbols that are described here have the same shape as the letter from which they are derived, such as and .

These letters alone are not sufficient for the needs of mathematicians, and many other symbols are used. Some take their origin in punctuation marks and diacritics traditionally used in typography; others by deforming letter forms, as in the cases of and . Others, such as +Script error: No such module "Check for unknown parameters". and =Script error: No such module "Check for unknown parameters"., were specially designed for mathematics.

Layout of this article

  • Normally, entries of a glossary are structured by topics and sorted alphabetically. This is not possible here, as there is no natural order on symbols, and many symbols are used in different parts of mathematics with different meanings, often completely unrelated. Therefore, some arbitrary choices had to be made, which are summarized below.
  • The article is split into sections that are sorted by an increasing level of technicality. That is, the first sections contain the symbols that are encountered in most mathematical texts, and that are supposed to be known even by beginners. On the other hand, the last sections contain symbols that are specific to some area of mathematics and are ignored outside these areas. However, the long section on brackets has been placed near to the end, although most of its entries are elementary: this makes it easier to search for a symbol entry by scrolling.
  • Most symbols have multiple meanings that are generally distinguished either by the area of mathematics where they are used or by their syntax, that is, by their position inside a formula and the nature of the other parts of the formula that are close to them.
  • As readers may not be aware of the area of mathematics to which the symbol that they are looking for is related, the different meanings of a symbol are grouped in the section corresponding to their most common meaning.
  • When the meaning depends on the syntax, a symbol may have different entries depending on the syntax. For summarizing the syntax in the entry name, the symbol is used for representing the neighboring parts of a formula that contains the symbol. See Template:Slink for examples of use.
  • Most symbols have two printed versions. They can be displayed as Unicode characters, or in LaTeX format. With the Unicode version, using search engines and copy-pasting are easier. On the other hand, the LaTeX rendering is often much better (more aesthetic), and is generally considered a standard in mathematics. Therefore, in this article, the Unicode version of the symbols is used (when possible) for labelling their entry, and the LaTeX version is used in their description. So, for finding how to type a symbol in LaTeX, it suffices to look at the source of the article.
  • For most symbols, the entry name is the corresponding Unicode symbol. So, for searching the entry of a symbol, it suffices to type or copy the Unicode symbol into the search textbox. Similarly, when possible, the entry name of a symbol is also an anchor, which allows linking easily from another Wikipedia article. When an entry name contains special characters such as [,], and |, there is also an anchor, but one has to look at the article source to know it.
  • Finally, when there is an article on the symbol itself (not its mathematical meaning), it is linked to in the entry name.

Arithmetic operators

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<dt id="Script error: No such module "delink"." >+Script error: No such module "Check for unknown parameters". Script error: No such module "String".(plus sign) Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(minus sign) Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >×Script error: No such module "Check for unknown parameters". Script error: No such module "String".(multiplication sign) Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >·Script error: No such module "Check for unknown parameters". Script error: No such module "String".(dot) Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >±Script error: No such module "Check for unknown parameters". Script error: No such module "String".(plus–minus sign) Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(minus–plus sign) Template:Defn <dt id="Script error: No such module "delink"." >÷Script error: No such module "Check for unknown parameters". Script error: No such module "String".(division sign) Template:Defn <dt id="Script error: No such module "delink"." >:Script error: No such module "Check for unknown parameters". Script error: No such module "String".(colon) Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >/Script error: No such module "Check for unknown parameters". Script error: No such module "String".(slash) Template:Defn Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(square-root symbol) Template:Defn <dt id="Script error: No such module "delink"." >  Script error: No such module "Check for unknown parameters". Script error: No such module "String".(radical symbol) Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >^Script error: No such module "Check for unknown parameters". Script error: No such module "String".(caret) Template:Defn Template:Defn

Equality, equivalence and similarity

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<dt id="Script error: No such module "delink"." >=Script error: No such module "Check for unknown parameters". Script error: No such module "String".(equals sign) Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >=def:= Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(not-equal sign) Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(approximately equals sign) Template:Defn <dt id="Script error: No such module "delink"." >~Script error: No such module "Check for unknown parameters". Script error: No such module "String".(tilde) Template:Defn Template:Defn Template:Defn Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(triple bar) Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." > Template:Defn Template:Defn

Comparison

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<dt id="Script error: No such module "delink"." ><Script error: No such module "Check for unknown parameters". Script error: No such module "String".(less-than sign) Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >>Script error: No such module "Check for unknown parameters". Script error: No such module "String".(greater-than sign) Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." > and  Template:Defn Template:Defn <dt id="Script error: No such module "delink"." > and  Template:Defn <dt id="Script error: No such module "delink"." > and  Template:Defn

Set theory

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<dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(null sign) Template:Defn <dt id="Script error: No such module "delink"." >#Script error: No such module "Check for unknown parameters". Script error: No such module "String".(number sign) Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >⊃, ⊇, ⊋Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(backslash) Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". or Template:Defn <dt id="Script error: No such module "delink"." > Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >×Script error: No such module "Check for unknown parameters". Script error: No such module "String".(multiplication sign) Template:Defn Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." > Template:Defn <dt id="Script error: No such module "delink"." > or  Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(Hiragana Yo) or h Template:Defn

Basic logic

Several logical symbols are widely used in all mathematics, and are listed here. For symbols that are used only in mathematical logic, or are rarely used, see List of logic symbols.

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<dt id="Script error: No such module "delink"." >¬Script error: No such module "Check for unknown parameters". Script error: No such module "String".(not sign) Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(descending wedge) Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(wedge) Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(turned A) Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >∃!Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(tee) Template:Defn Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(up tack) Template:Defn Template:Defn Template:Defn Template:Defn Template:Defn Template:Defn

Blackboard bold

The blackboard bold typeface is widely used for denoting the basic number systems. These systems are often also denoted by the corresponding uppercase bold letter. A clear advantage of blackboard bold is that these symbols cannot be confused with anything else. This allows using them in any area of mathematics, without having to recall their definition. For example, if one encounters in combinatorics, one should immediately know that this denotes the real numbers, although combinatorics does not study the real numbers (but it uses them for many proofs). <templatestyles src="Glossary/styles.css" />

<dt id="Script error: No such module "delink"." > Template:Defn <dt id="Script error: No such module "delink"." > Template:Defn <dt id="Script error: No such module "delink"." >p Template:Defn Template:Defn <dt id="Script error: No such module "delink"." > Template:Defn <dt id="Script error: No such module "delink"." >p Template:Defn <dt id="Script error: No such module "delink"." > Template:Defn <dt id="Script error: No such module "delink"." > Template:Defn <dt id="Script error: No such module "delink"." > Template:Defn <dt id="Script error: No such module "delink"." >𝔽q Template:Defn <dt id="Script error: No such module "delink"." >𝕆 Template:Defn <dt id="Script error: No such module "delink"." >𝕊 Template:Defn <dt id="Script error: No such module "delink"." >𝕋 Template:Defn

Calculus

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<dt id="Script error: No such module "delink"." >Template:'Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >˙ Template:Defn <dt id="Script error: No such module "delink"." >¨ Template:Defn <dt id="Script error: No such module "delink"." >Template:SfracScript error: No such module "Check for unknown parameters". Template:Defn Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Template:SfracScript error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Template:SfracScript error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." > Template:Defn Template:Defn Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters".[1] Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >∬, ∯Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >∭, ∰Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." > or Template:Defn or the covariant derivative. <dt id="Script error: No such module "delink"." >2Script error: No such module "Check for unknown parameters". or ∇⋅∇Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >ΔScript error: No such module "Check for unknown parameters". (Capital Greek letter delta—not to be confused with , which may denote a geometric triangle or, alternatively, the symmetric difference of two sets.) Template:Defn Template:Defn <dt id="Script error: No such module "delink"." > or μ (Note: Although    may be used unambiguously, the notation is not recommended for the four-gradient since both and 2 are used to denote the d'Alembertian; see below.) Template:Defn <dt id="Script error: No such module "delink"." > or 2 (here the symbol is an actual box, not a placeholder) Template:Defn

Linear and multilinear algebra

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<dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Script error: No such module "String".(capital-sigma notation) Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters".Script error: No such module "String". (capital-pi notation) Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." > Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." > Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn Template:Defn

Advanced group theory

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<dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters".Script error: No such module "string".Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters".Script error: No such module "string".Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn

Infinite numbers

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<dt id="Script error: No such module "delink"." > Script error: No such module "String".(infinity symbol) Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >𝔠Script error: No such module "String".(fraktur 𝔠) Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "String".(aleph) Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "String".(bet (letter)) Template:Defn <dt id="Script error: No such module "delink"." >ωScript error: No such module "String".(omega) Template:Defn Template:Defn Template:Defn Template:Defn Template:Defn

Brackets

Many types of bracket are used in mathematics. Their meanings depend not only on their shapes, but also on the nature and the arrangement of what is delimited by them, and sometimes what appears between or before them. For this reason, in the entry titles, the symbol Script error: No such module "Check for unknown parameters". is used as a placeholder for schematizing the syntax that underlies the meaning.

Parentheses

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<dt id="Script error: No such module "delink"." >(□)Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >□(□)Script error: No such module "Check for unknown parameters".Script error: No such module "string".□(□, □)Script error: No such module "Check for unknown parameters".Script error: No such module "string".□(□, ..., □)Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >(□, □)Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >(□, □, □)Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >(□, ..., □)Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >(□, □, ...)Script error: No such module "Check for unknown parameters".Script error: No such module "string".(□, ..., □, ...)Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >() Template:Defn <dt id="Script error: No such module "delink"." >() Template:Defn <dt id="Script error: No such module "delink"." >() Template:Defn

Square brackets

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<dt id="Script error: No such module "delink"." >[□]Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >□[□]Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >[□, □]Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >[□ : □]Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >[□, □, □]Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >[] Template:Defn

Braces

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<dt id="Script error: No such module "delink"." >Template:MsetScript error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Template:Brace Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Template:Brace Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Template:Brace Script error: No such module "Check for unknown parameters".Script error: No such module "string".Template:Brace Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Single brace Template:Defn Template:Defn Template:Defn

Other brackets

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<dt id="Script error: No such module "delink"." >|□|Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Template:AbsScript error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >|| Template:Defn <dt id="Script error: No such module "delink"." >||□||Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >⌊□⌋Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >⌈□⌉Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >⌊□⌉Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >]□, □[Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >(□, □]Script error: No such module "Check for unknown parameters".Script error: No such module "string".]□, □]Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >[□, □)Script error: No such module "Check for unknown parameters".Script error: No such module "string".[□, □[Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >⟨□⟩Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >⟨□, □⟩Script error: No such module "Check for unknown parameters".Script error: No such module "string".⟨□ | □⟩Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >| and | Template:Defn

Symbols that do not belong to formulas

In this section, the symbols that are listed are used as some sorts of punctuation marks in mathematical reasoning, or as abbreviations of natural language phrases. They are generally not used inside a formula. Some were used in classical logic for indicating the logical dependence between sentences written in plain language. Except for the first two, they are normally not used in printed mathematical texts since, for readability, it is generally recommended to have at least one word between two formulas. However, they are still used on a black board for indicating relationships between formulas.

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<dt id="Script error: No such module "delink"." >■ , □Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn

Miscellaneous

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<dt id="Script error: No such module "delink"." >!Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >*Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >|Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn Template:Defn Template:Defn Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." > Template:Defn Template:Defn <dt id="Script error: No such module "delink"." >Script error: No such module "Check for unknown parameters". Template:Defn <dt id="Script error: No such module "delink"." >Ш Template:Defn

See also

Related articles

Related lists

Unicode symbols

References

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  1. The LaTeX equivalent to both Unicode symbols ∘ and ○ is \circ. The Unicode symbol that has the same size as \circ depends on the browser and its implementation. In some cases ∘ is so small that it can be confused with an interpoint, and ○ looks similar as \circ. In other cases, ○ is too large for denoting a binary operation, and it is ∘ that looks like \circ. As LaTeX is commonly considered as the standard for mathematical typography, and it does not distinguish these two Unicode symbols, they are considered here as having the same mathematical meaning.

Script error: No such module "Check for unknown parameters".

External links

Some Unicode charts of mathematical operators and symbols:
Some Unicode cross-references:

Script error: No such module "Navbox". Template:Mathematical symbols notation language