(mathbb N): The set of natural numbers (0,1,2,3,…)
(mathbb Q): The set of rational numbers.
(mathbb R): The set of real numbers.
(mathbb Z): The set of integer numbers (…,-3,-2,-1,0, 1,2,3,…)
A
B
C
D
E
F
G
H
I
Integer: a number of the set (mathbb Z=lbrace …,-3,-2,-1,0,1,2,3,…rbrace)
J
K
L
M
N
Natural number: a number of the set (mathbb N=lbrace 0,1,2,3,…rbrace)
O
P
Q
R
Rational number: a number of the set (mathbb Q=lbrace …frac ab:, ainmathbb Z, binmathbb Nrbrace)
Real number: an element of (mathbb R). The set (mathbb R) contains the limits of sequences of rational numbers and elements like square roots, (pi, e,…)
S
Square root of (xge 0): the positive number (y) satisfying (y^2=x).
(m-)th square root of (xge 0): the positive number (y) satisfying (y^m=x).