Algebraic Symbols

Question 1

≜

Answer 1

equal by definition

Question 2

≡

Answer 2

identical to

Question 3

Answer 3

proportional to

y ∝ x when y = kx, k constant

Question 4

⌊x⌋

Answer 4

floor brackets

floor brackets rounds number to lower integer

⌊4.3⌋= 4

Question 5

⌈x⌉

Answer 5

ceiling brackets

rounds number to upper integer

⌈4.3⌉= 5

Question 6

(a,b)

Answer 6

open interval

(a,b) = {x | a < x < b}

Question 7

[a,b]

Answer 7

closed interval

[a,b] = {x | a ≤ x ≤ b}

Question 8

∆

Answer 8

discriminant

could also be “delta”

Question 9

∑

Answer 9

Sigma Notation

Also known as Summation

Question 10

∑∑

Answer 10

Double Summation

Question 11

∏

Answer 11

Capital Pi

∏ xi=x1∙x2∙…∙xn

Question 12

∞

Answer 12

Lemniscate

Question 13

e

Answer 13

Euler’s Number

e = 2.718281828…

Question 14

γ

Answer 14

Euler-Mascheroni constant

constant γ = 0.5772156649…

Question 15

φ

Answer 15

Golden Ratio

approximately 1.618

Question 16

π

Answer 16

Pi Constant

π = 3.141592654…

Question 17

{ }

Answer 17

Set

in relation to “Set Theory”

Question 18

∀

Answer 18

“For All/Any”

∀ squares D, D is a rectangle

Question 19

∃

Answer 19

There exists

∃x∈N:x is even

Question 20

3√

Answer 20

Cube Root

We use the cube root symbol in the following way. ∛27 = 3

Question 21

4√

Answer 21

Fourth Root

The fourth root of 16 is 2, i.e. 2 × 2 × 2 × 2 = 16.

Question 22

〈x, y〉

Answer 22

Inner Product

Question 23

| A |

Answer 23

Determinant of Matrix A

Question 24

Answer 24

Matrix Transpose

Is formed by turning all the rows of a matrix into columns and viceversa

Question 25

Answer 25

Matrix Inverse

The inverse of a square matrix A, sometimes called a Matrix Inverse.