ABSTRACT
Consider a set of N real numbers denoted by
. (7.1.1)
The symbol
A
consisting of a kernel letter and a letter subscript will denote a typical one of these numbers. To denote a particular one of the numbers, we assign a numerical value to the subscript:
i
= 1, 2, 3, …,
N
. Similarly,
A
with
i
and
j
ranging from 1 to 3 denotes any one of the nine numbers denoted by
, (7.1.2)
depending upon the numerical value assigned to the subscripts. This system can be extended to any number of superscripts or subscripts, which we will call indices. The range for each index must be specified.
