Subsets of Real Numbers
Natural Numbers -are used for counting and the set does not include zero.
Whole Numbers – include the set of natural numbers and zero.
Integers – includes zero, the set of natural numbers, commonly called the positive integers and the opposite of the natural numbers.
Rational Numbers – include any number that can be represented by the quotient of two integers. In that quotient the denominator must not be zero.
Given that a and b are integers, then where .
There are all kinds of numbers that fit this description. Any combination of the fractions with the subsets above fit the definition of a rational number.
It is good to remember that all numbers that are termination decimals such as and .
Let’s not for get those decimals that have a pattern that can be identified as repeating. Here are just two examples: and .
Irrational Numbers – , , , ,
These are just a few of the examples of irrational numbers. If a number does not fit in as one of the other numbers, it is irrational. There is another set of numbers to, but that is another topic for another day.