Real numbers have the following five subsets:
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Natural numbers: These are also called “counting numbers”. They start
with “1” and keep going: {1, 2, 3, 4, 5, ….}”
Whole numbers: The set of natural numbers mentioned above, along
with 0: {0, 1, 2, 3, 4, 5 ….}
Integers: All whole numbers, along with negative numbers, make up the
set of integers, like: -3, -2, -1, 0, 1, 2, 3
Rational numbers: Numbers that can be written in the form of a simple
fraction with 2 integers, like: 1/9, 0, -6, 5/6, 3.23, -2/11.
Irrational numbers: Numbers that run on forever without repeating any
sequences. They include square roots of positive rational numbers, such
as √2 and √11, and certain mathematical values like π (3.14159……).