Algebra Symbols

List of mathematical algebra symbols and signs.

Algebra math symbols table

Symbol	Symbol Name	Meaning / definition	Example
x	x variable	unknown value to find	when 2x = 4, then x = 2
≡	equivalence	identical to
≜	equal by definition	equal by definition
~	approximately equal	weak approximation	11 ~ 10
≈	approximately equal	approximation	sin(0.01) ≈ 0.01
∝	proportional to	proportional to	f(x) ∝ g(x)
∞	lemniscate	infinity symbol
≪	much less than	much less than	1 ≪ 1000000
≫	much greater than	much greater than	1000000 ≫ 1
( )	parentheses	calculate expression inside first	2 * (3+5) = 16
[ ]	brackets	calculate expression inside first	[(1+2)*(1+5)] = 18
{ }	braces	set
⌊x⌋	floor brackets	rounds number to lower integer	⌊4.3⌋= 4
⌈x⌉	ceiling brackets	rounds number to upper integer	⌈4.3⌉= 5
x!	exclamation mark	factorial	4! = 1*2*3*4 = 24
| x |	single vertical bar	absolute value	| -5 | = 5
f (x)	function of x	maps values of x to f(x)	f (x) = 3x+5
(a,b)	open interval	(a,b) ≜ {x | a < x < b}	x ∈ (2,6)
[a,b]	closed interval	[a,b] ≜ {x | a ≤ x ≤ b}	x ∈ [2,6]
∆	delta	change / difference	∆t = t1 - t0
∆	discriminant	Δ = b2 - 4ac
∑	sigma	summation - sum of all values in range of series	∑ xi= x1+x2+...+xn
∑∑	sigma	double summation
∏	capital pi	product - product of all values in range of series	∏ xi=x1∙x2∙...∙xn
e	e constant / Euler's number	e = 2.718281828...	e = lim (1+1/x)x , x→∞
γ	Euler-Mascheroni  constant	γ = 0.527721566...
φ	golden ratio	golden ratio constant
π	pi constant	π = 3.141592654... is the ratio between circle's perimeter and circumference	P = 2·π·r

Linear Algebra Symbols

Symbol	Symbol Name	Meaning / definition	Example
∙	dot	scalar product	a ∙ b
×	cross	vector product	a × b
	inner product
[ ]	brackets	matrix of numbers
( )	parentheses	matrix of numbers
| A |	vertical bars	determinant
|| x ||	double vertical bars	norm
A T	matrix transpose	(aij=aji)
A -1	inverse matrix	A A-1 = I
rank(A)	matrix rank		rank(A) = 3
dim(U)	dimension

 

Statistical symbols ►

 

---

See also

• Math symbols
• Basic math symbols
• Statistical symbols
• Set symbols
• Calculus symbols