Notation

A real number can be represented in different ways. As mentioned before, a rational number (which is also a real number) can be expressed as an integer, as a quotient of two integers, and thus as a fraction (two integers separated by a "/"), or as a terminating or repeating decimal. Irrational numbers can have the form of fractions (where the numerator and/or denominator are not integers) or of non-repeating decimals. Real numbers can also be represented by expressions involving exponents and/or radicals, as well as by special symbols. The following are examples of real number representations:

4 = ( 8 / 2 ) = 4.00 = 2²
( 1 / 6 ) = 0.166666......
p = 3.14159265358979....
e = 2.718281828459....

Real numbers can also be expressed in scientific and/or set notation. Scientific notation is used for individual real numbers, while set notation is used to indicate groups of real numbers.