The Real Number System

Infinity (oo) is not a real number. It is possible to extend the real-number system by adjoiutiug to it oo and and within the... 

In the real-number system a greater than h a > b) and b less than c(b < c) define an order relation. These relations have no meaning for complex numbers. The absolute value is used for ordering. Some important relations follow bl > x bl > y z Z9 z- + bgl bi - Zol Ibil — zo z- > (bl -I- lyl)/V2. Parts of the complex plane, commonly called regions or domains, are described by using inequalities. 

To put it briefly, geometric algebra [32-35] is an extension of the real number system to incorporate the geometric concept of direction that is, it is a system of directed numbers. Geometric algebra integrates the well-established branches... 

Numerical approximation was closely related to the development of the real number system until the work of Sir Issac Newton, then with astronomy and physics, and after the 1950 s with computers. 

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