Numbers and Sets |
About Algebra
Addition and Subtraction Multiplication and Division Criterions for Divisibility
Types of Numbers Geometric Interpretation of Real Numbers Irrational Number Properties of Real Numbers Fractions Proportions Property of Equal Proportions Absolute Values Graphical Illustrations
Sets Subsets Operations with Sets Intervals |
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Note that any natural number is also integer.
Even
numbers are divisible by 2. Odd
numbers are leaving a remainder of 1 when divided by 2. A number is called a rational number, if it can be written as a quotient of two integers, p and q. Note that any integer can be written as a quotient of the integer itself and 1. So integers are also rational numbers. A rational number can be also represented by a terminating decimal or a recurring decimal, for instance, An irrational number can
be represented by non-repeating and non-terminating decimal. It is not
capable of being expressed exactly as a ratio of two integers. .
The rational and irrational numbers form together the set of real numbers. The number zero is used
as the origin, and any numbers can be compared with zero. |