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Numbers of Algebra

The study of algebra requires that you know the specifi c names of numbers.

In this chapter, you learn about the various sets of numbers that make up

the real numbers.

Natural Numbers, Whole Numbers, and Integers

The natural numbers (or counting numbers) are the

numbers in the set

N = (^) {} 12 ,,, 23453 ,,,,, 5676788 ...
You can represent the natural numbers as equally spaced points on a number
line, increasing endlessly in the direction of the arrow, as shown in Figure 1.1.
The sum of any two natural numbers is also a natural number. For
example, 355 = 8. Similarly, the product of any two natural numbers is also
a natural number. For example, 255 = 10. However, if you subtract or divide
two natural numbers, your result is not always
a natural number. For instance, 855 = 3 is a
natural number, but 58 is not.
The three dots indicate
that the pattern
continues without end.
You do not get a natural number as the
answer when you subtract a larger natural
number from a smaller natural number.
1 2 384 5 67
Figure 1.1 Natural numbers