Let's start from scratch:
This is what it looks like when we use indices:
What does this mean?
BLUE BACKROUND
MEANS CLICK |
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BLUE BACKROUND
MEANS CLICK
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Indices describe repeated multiplication.
- 3 is the base. All the factors are 3.
- 4 is the index. It tells us how many factors there are.
This is the definition of indices. We will call it
definiton 1.
Here is a different definition (definition 2).
This says to start with 1. Then you multiply 1 by
the base (3) as many times as the index says (4).
We will find both definitions useful.
These definitions are prototype definitions.
- We used 3 for the base, but the base can be any number.
- We used 4 for the index. This must be a counting number or postive
integer. (We will remove this restriction in the next section).
Sometimes we need formal definitions. These are very precise statements
which usually involve algebra so as to be general. Often its good
to leave formal definitions until later, when you will have a better
idea of what they are on about. So its up to you. Check them out
now or leave them until later..
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