List of mathematical symbols

This is a listing of common symbols found within all branches of mathematics. Each symbol is listed in both HTML, which depends on appropriate fonts being installed, and in TeX, as an image.

This list is incomplete; you can help by expanding it.

1 Symbols
2 Variations
3 See also
4 References
5 External links

Symbols

Symbol in HTML	Symbol in TeX	Name	Explanation	Examples
		Read as
		Category
=	$= \!\,$	equality is equal to; equals everywhere	x = y means x and y represent the same thing or value.	2 = 2 1 + 1 = 2
≠	$\ne \!\,$	inequality is not equal to; does not equal everywhere	x ≠ y means that x and y do not represent the same thing or value. (The forms !=, /= or <> are generally used in programming languages where ease of typing and use of ASCII text is preferred.)	2 + 2 ≠ 5
< >	$< \!\,$ $> \!\,$	strict inequality is less than, is greater than order theory	x < y means x is less than y. x > y means x is greater than y.	3 < 4 5 > 4
< >	$< \!\,$ $> \!\,$	proper subgroup is a proper subgroup of group theory	H < G means H is a proper subgroup of G.	5Z < Z A₃ < S₃
≪ ≫	$\ll \!\,$ $\gg \!\,$	(very) strict inequality is much less than, is much greater than order theory	x ≪ y means x is much less than y. x ≫ y means x is much greater than y.	0.003 ≪ 1000000
≪ ≫	$\ll \!\,$ $\gg \!\,$	asymptotic comparison is of smaller order than, is of greater order than analytic number theory	f ≪ g means the growth of f is asymptotically bounded by g. (This is I. M. Vinogradov's notation. Another notation is the Big O notation, which looks like f = O(g).)	x ≪ e^x
≤ ≥	$\le \!\,$ $\ge \!\,$	inequality is less than or equal to, is greater than or equal to order theory	x ≤ y means x is less than or equal to y. x ≥ y means x is greater than or equal to y. (The forms <= and >= are generally used in programming languages where ease of typing and use of ASCII text is preferred.)	3 ≤ 4 and 5 ≤ 5 5 ≥ 4 and 5 ≥ 5
		subgroup is a subgroup of group theory	H ≤ G means H is a subgroup of G.	Z ≤ Z A₃ ≤ S₃
		reduction is reducible to computational complexity theory	A ≤ B means the problem A can be reduced to the problem B. Subscripts can be added to the ≤ to indicate what kind of reduction.	If $\exists f \in F \mbox{ . } \forall x \in \mathbb{N} \mbox{ . } x \in A \Leftrightarrow f(x) \in B$ then $A \leq_{F} B$
≺	$\prec \!\,$	Karp reduction is Karp reducible to; is polynomial-time many-one reducible to computational complexity theory	L₁ ≺ L₂ means that the problem L₁ is Karp reducible to L₂.^[1]	If L₁ ≺ L₂ and L₂ ∈ P, then L₁ ∈ P.
∝	$\propto \!\,$	proportionality is proportional to; varies as everywhere	y ∝ x means that y = kx for some constant k.	if y = 2x, then y ∝ x.
∝	$\propto \!\,$	Karp reduction^[2] is Karp reducible to; is polynomial-time many-one reducible to computational complexity theory	A ∝ B means the problem A can be polynomially reduced to the problem B.	If L₁ ∝ L₂ and L₂ ∈ P, then L₁ ∈ P.
+	$+ \!\,$	addition plus; add arithmetic	4 + 6 means the sum of 4 and 6.	2 + 7 = 9
+	$+ \!\,$	disjoint union the disjoint union of ... and ... set theory	A₁ + A₂ means the disjoint union of sets A₁ and A₂.	A₁ = {3, 4, 5, 6} ∧ A₂ = {7, 8, 9, 10} ⇒ A₁ + A₂ = {(3,1), (4,1), (5,1), (6,1), (7,2), (8,2), (9,2), (10,2)}
−	$- \!\,$	subtraction minus; take; subtract arithmetic	9 − 4 means the subtraction of 4 from 9.	8 − 3 = 5
		negative sign negative; minus; the opposite of arithmetic	−3 means the negative of the number 3.	−(−5) = 5
		set-theoretic complement minus; without set theory	A − B means the set that contains all the elements of A that are not in B. (∖ can also be used for set-theoretic complement as described below.)	{1,2,4} − {1,3,4} = {2}
±	$\pm \!\,$	plus-minus plus or minus arithmetic	6 ± 3 means both 6 + 3 and 6 − 3.	The equation x = 5 ± √4, has two solutions, x = 7 and x = 3.
±	$\pm \!\,$	plus-minus plus or minus measurement	10 ± 2 or equivalently 10 ± 20% means the range from 10 − 2 to 10 + 2.	If a = 100 ± 1 mm, then a ≥ 99 mm and a ≤ 101 mm.
∓	$\mp \!\,$	minus-plus minus or plus arithmetic	6 ± (3 ∓ 5) means both 6 + (3 − 5) and 6 − (3 + 5).	cos(x ± y) = cos(x) cos(y) ∓ sin(x) sin(y).
×	$\times \!\,$	multiplication times; multiplied by arithmetic	3 × 4 means the multiplication of 3 by 4. (The symbol * is generally used in programming languages, where ease of typing and use of ASCII text is preferred.)	7 × 8 = 56
		Cartesian product the Cartesian product of ... and ...; the direct product of ... and ... set theory	X×Y means the set of all ordered pairs with the first element of each pair selected from X and the second element selected from Y.	{1,2} × {3,4} = {(1,3),(1,4),(2,3),(2,4)}
		cross product cross linear algebra	u × v means the cross product of vectors u and v	(1,2,5) × (3,4,−1) = (−22, 16, − 2)
		group of units the group of units of ring theory	R^× consists of the set of units of the ring R, along with the operation of multiplication. This may also be written R* as described below, or U(R).	$\begin{align} (\mathbb{Z} / 5\mathbb{Z})^\times & = \{ [1], [2], [3], [4] \} \\ & \cong C_4 \\ \end{align}$
*	$* \!\,$	multiplication times; multiplied by arithmetic	a * b means the product of a and b. (Multiplication can also be denoted with × or ⋅, or even simple juxtaposition. * is generally used where ease of typing and use of ASCII text is preferred, such as programming languages.)	4 * 3 means the product of 4 and 3, or 12.
		convolution convolution; convolved with functional analysis	f * g means the convolution of f and g.	$(f * g)(t) = \int_{-\infty}^{\infty} f(\tau) g(t - \tau)\, d\tau$ .
		complex conjugate conjugate complex numbers	z* means the complex conjugate of z. ( $\bar{z}$ can also be used for the conjugate of z, as described below.)	$(3+4i)^\ast = 3-4i$ .
		group of units the group of units of ring theory	R* consists of the set of units of the ring R, along with the operation of multiplication. This may also be written R^× as described above, or U(R).	$\begin{align} (\mathbb{Z} / 5\mathbb{Z})^\ast & = \{ [1], [2], [3], [4] \} \\ & \cong C_4 \\ \end{align}$
		hyperreal numbers the (set of) hyperreals non-standard analysis	*R means the set of hyperreal numbers. Other sets can be used in place of R.	*N is the hypernatural numbers.
		Hodge dual Hodge dual; Hodge star linear algebra	v means the Hodge dual of a vector v. If v is a k-vector within an n-dimensional oriented inner product space, then v is an (n−k)-vector.	If ${e i}$ are the standard basis vectors of $\mathbb{R}^5$ , $*(e_1\wedge e_2\wedge e_3)= e_4\wedge e_5$
·	$\cdot \!\,$	multiplication times; multiplied by arithmetic	3 · 4 means the multiplication of 3 by 4.	7 · 8 = 56
·	$\cdot \!\,$	dot product dot linear algebra	u · v means the dot product of vectors u and v	(1,2,5) · (3,4,−1) = 6
⊗	$\otimes \!\,$	tensor product, tensor product of modules tensor product of linear algebra	$V \otimes U$ means the tensor product of V and U.^[3] $V \otimes_R U$ means the tensor product of modules V and U over the ring R.	{1, 2, 3, 4} ⊗ {1, 1, 2} = {{1, 2, 3, 4}, {1, 2, 3, 4}, {2, 4, 6, 8}}
÷ ⁄	$\div \!\,$ $/ \!\,$	division (Obelus) divided by; over arithmetic	6 ÷ 3 or 6 ⁄ 3 means the division of 6 by 3.	2 ÷ 4 = 0.5 12 ⁄ 4 = 3
		quotient group mod group theory	G / H means the quotient of group G modulo its subgroup H.	{0, a, 2a, b, b+a, b+2a} / {0, b} = {{0, b}, {a, b+a}, {2a, b+2a}}
		quotient set mod set theory	A/~ means the set of all ~ equivalence classes in A.	If we define ~ by x ~ y ⇔ x − y ∈ ℤ, then ℝ/~ = {x + n : n ∈ ℤ : x ∈ (0,1]}
√	$\surd \!\,$ $\sqrt{\ } \!\,$	square root the (principal) square root of real numbers	$\sqrt{x}$ means the nonnegative number whose square is $x$ .	$\sqrt{4}=2$
√	$\surd \!\,$ $\sqrt{\ } \!\,$	complex square root the (complex) square root of complex numbers	if $z=r\,\exp(i\phi)$ is represented in polar coordinates with $-\pi < \phi \le \pi$ , then $\sqrt{z} = \sqrt{r} \exp(i \phi/2)$ .	$\sqrt{-1}=i$
x	$\bar{x} \!\,$	mean overbar; … bar statistics	$\bar{x}$ (often read as “x bar”) is the mean (average value of $x i$ ).	$x = \{1,2,3,4,5\}; \bar{x} = 3$ .
		complex conjugate conjugate complex numbers	$\overline{z}$ means the complex conjugate of z. (z* can also be used for the conjugate of z, as described above.)	$\overline{3+4i} = 3-4i$ .
		algebraic closure algebraic closure of field theory	$\overline{F}$ is the algebraic closure of the field F.	The field of algebraic numbers is sometimes denoted as $\overline{\mathbb{Q}}$ because it is the algebraic closure of the rational numbers ${\mathbb{Q}}$ .
		topological closure (topological) closure of topology	$\overline{S}$ is the topological closure of the set S. This may also be denoted as cl(S) or Cl(S).	In the space of the real numbers, $\overline{\mathbb{Q}} = \mathbb{R}$ (the rational numbers are dense in the real numbers).
\|…\|	$\| \ldots \| \!\,$	absolute value; modulus absolute value of; modulus of numbers	\|x\| means the distance along the real line (or across the complex plane) between x and zero.	\|3\| = 3 \|–5\| = \|5\| = 5 \| i \| = 1 \| 3 + 4i \| = 5
		Euclidean norm or Euclidean length or magnitude Euclidean norm of geometry	\|x\| means the (Euclidean) length of vector x.	For x = (3,-4) $\|\textbf{x}\| = \sqrt{3^2 + (-4)^2} = 5$
		determinant determinant of matrix theory	\|A\| means the determinant of the matrix A	$\begin{vmatrix} 1&2 \\ 2&9 \\ \end{vmatrix} = 5$
		cardinality cardinality of; size of; order of set theory	\|X\| means the cardinality of the set X. (# may be used instead as described below.)	\|{3, 5, 7, 9}\| = 4.
\|\|…\|\|	$\\| \ldots \\| \!\,$	norm norm of; length of linear algebra	\|\| x \|\| means the norm of the element x of a normed vector space.^[4]	\|\| x + y \|\| ≤ \|\| x \|\| + \|\| y \|\|
\|\|…\|\|	$\\| \ldots \\| \!\,$	nearest integer function nearest integer to numbers	\|\|x\|\| means the nearest integer to x. (This may also be written [x], ⌊x⌉, nint(x) or Round(x).)	\|\|1\|\| = 1, \|\|1.6\|\| = 2, \|\|−2.4\|\| = −2, \|\|3.49\|\| = 3
∣ ∤	$\mid \!\,$ $\nmid \!\,$	divisor, divides divides number theory	a\|b means a divides b. a∤b means a does not divide b. (This symbol can be difficult to type, and its negation is rare, so a regular but slightly shorter vertical bar \| character can be used.)	Since 15 = 3×5, it is true that 3\|15 and 5\|15.
		conditional probability given probability	P(A\|B) means the probability of the event a occurring given that b occurs.	if X is a uniformly random day of the year P(X is May 25 \| X is in May) = 1/31
		restriction restriction of … to …; restricted to set theory	f\|_A means the function f restricted to the set A, that is, it is the function with domain A ∩ dom(f) that agrees with f.	The function f : R → R defined by f(x) = x² is not injective, but f\|_R⁺ is injective.
		such that such that; so that everywhere	\| means “such that”, see ":" (described below).	S = {(x,y) \| 0 < y < f(x)} The set of (x,y) such that y is greater than 0 and less than f(x).
\|\|	$\\| \!\,$	parallel is parallel to geometry	x \|\| y means x is parallel to y.	If l \|\| m and m ⊥ n then l ⊥ n.
		incomparability is incomparable to order theory	x \|\| y means x is incomparable to y.	{1,2} \|\| {2,3} under set containment.
		exact divisibility exactly divides number theory	p^a \|\| n means p^a exactly divides n (i.e. p^a divides n but p^a+1 does not).	2³ \|\| 360.
#	$\# \!\,$	cardinality cardinality of; size of; order of set theory	#X means the cardinality of the set X. (\|…\| may be used instead as described above.)	#{4, 6, 8} = 3
#	$\# \!\,$	connected sum connected sum of; knot sum of; knot composition of topology, knot theory	A#B is the connected sum of the manifolds A and B. If A and B are knots, then this denotes the knot sum, which has a slightly stronger condition.	A#S^m is homeomorphic to A, for any manifold A, and the sphere S^m.
ℵ	$\aleph \!\,$	aleph number aleph set theory	ℵ_α represents an infinite cardinality (specifically, the α-th one, where α is an ordinal).	\|ℕ\| = ℵ₀, which is called aleph-null.
ℶ	$\beth \!\,$	beth number beth set theory	ℶ_α represents an infinite cardinality (similar to ℵ, but ℶ does not necessarily index all of the numbers indexed by ℵ. ).	$\beth_1 = \|P(\mathbb{N})\| = 2^{\aleph_0}.$
Wikimedia Foundation. 2010. Игры ⚽ Нужен реферат? Math the Band Floating-point unit Look at other dictionaries: List of mathematical logic topics — Clicking on related changes shows a list of most recent edits of articles to which this page links. This page links to itself in order that recent changes to this page will also be included in related changes. This is a list of mathematical logic … Wikipedia Wikipedia:Mathematical symbols — Shortcut: WP:MATHSYMBOL This page is a quick reference for the standard mathematical symbols in HTML that should work on most browsers, and is intended mainly for people editing mathematical articles on Wikipedia. Numbers: ¼ ½ ¾ frac14; frac12;… … Wikipedia Mathematical logic — (also known as symbolic logic) is a subfield of mathematics with close connections to foundations of mathematics, theoretical computer science and philosophical logic.[1] The field includes both the mathematical study of logic and the… … Wikipedia Mathematical notation — For information on rendering mathematical formulas in Wikipedia, see Help:Formula. See also: Table of mathematical symbols Mathematical notation is a system of symbolic representations of mathematical objects and ideas. Mathematical notations are … Wikipedia Mathematical operators and symbols in Unicode — ⊙ redirects here. For the similar symbol ☉, see Sun. Unicode ranges mathematical operators and symbols in multiple blocks. Mathematical Operators (U+2200–U+22FF) Miscellaneous Mathematical Symbols A (U+27C0–U+27EF) Miscellaneous Mathematical… … Wikipedia List of typefaces — This is a list of typefaces, which are separated into groups by distinct artistic differences. Contents 1 Serif 1.1 Slab serif 2 Sans serif 3 Semi serif … Wikipedia Mathematical proof — In mathematics, a proof is a convincing demonstration (within the accepted standards of the field) that some mathematical statement is necessarily true.[1][2] Proofs are obtained from deductive reasoning, rather than from inductive or empirical… … Wikipedia List of symbols — This is a list of graphical signs, icons, and symbols. Contents 1 Pictograms 2 Scientific and engineering symbols 3 Consumer symbols … Wikipedia List of mathematics articles (T) — NOTOC T T duality T group T group (mathematics) T integration T norm T norm fuzzy logics T schema T square (fractal) T symmetry T table T theory T.C. Mits T1 space Table of bases Table of Clebsch Gordan coefficients Table of divisors Table of Lie … Wikipedia Mathematical formulation of quantum mechanics — Quantum mechanics Uncertainty principle … Wikipedia 18+ © Academic, 2000-2024 Contact us: Technical Support, Advertising Dictionaries export, created on PHP, Joomla, Drupal, WordPress, MODx. Mark and share Search through all dictionaries Translate… Search Internet Share the article and excerpts Direct link … Do a right-click on the link above and select “Copy Link”