|
The set of real numbers consists of the set of rational numbers
and the set of irrational numbers. The set of rational numbers
has several subsets of numbers: the natural numbers, the whole numbers,
the integers and the rationals.
NATURAL NUMBERS
The set of natural numbers are the counting numbers
(1, 2, 3, ...…)
and is the first set of numbers that children learn. The set of natural
numbers is denoted  .
WHOLE NUMBERS
The set of whole numbers contains the set of natural numbers and
the number zero.
INTEGERS
The set of integers contains the set of whole numbers and their negatives
( ..., -2, -1, 0, 1, 2, 3, ... ). The set of integers is denoted Z
.
RATIONAL NUMBERS
The set of rational numbers contains all the possible ratios of
two integers a/b where b is not zero. The set of rational numbers
is denoted  .
IRRATIONAL NUMBERS
The set of irrational numbers
contains all the numbers which are not rational numbers. The most famous
examples are  and e.
Note that all real numbers are either rational or irrational.
|