# Table Of Algebra Symbols with Examples   ## Math Algebra Symbols with Examples

Symbol Symbol Name Symbol Meaning Example x x Variable unknown value to find when 3x = 9, thenx = 3
Congruence Relation identical to 5 2 (mod 3)
Is Equal By Definition is equal by definition ab Is Equal By Definition is equal by definition A B
:= Is Equal By Definition is equal by definition a:=b
~ Approximately Equal is similar to ∆ABC ~ ∆DEF means triangle ABC is similar to triangle DEF.
Approximately Equal approximation Is Proportional to is proportional to y x means, when y = kx, k constant
Lemniscate infinity symbol 1 / 0 = ∞
Much Less Than x y means x is much less than y. 0.0011000000
Much Greater Than x y means x is much greater than y. 1000000 0.001
( ) Parentheses calculate expression inside first 3 * (3+3) = 18
[ ] Brackets calculate expression inside first [(1+1)*(1+1)] = 4
{ } Braces set {..., -3,-2,-1,0,1,2,3, ... }
x Floor Brackets rounds number to lower integer 5.4= 5
x Ceiling Brackets rounds number to upper integer 5.4= 6
x! Exclamation Mark factorial 3! = 1*2*3 = 6
| x | Single Vertical Bar absolute value | -8 | = 8
f (x) Function of x maps values of x to f(x) f (x) = 2x+3
(f g) Function Composition

(f g) (x) = f (g(x))

f (x)=3x, g(x)=x-1 (f g)(x)=3(x-1)
(a,b) Open Interval (a,b) = {x | a < x < b} x (3,9)
[a,b] Closed Interval [a,b] = {x | axb} x [3,9]
Delta change / difference t = t1 - t0
Discriminant Δ = b2 - 4ac ∆ = 52-4(1)(4), = 25 - 16 , = 9
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 the circumference and diameter of a circle  