can you explain function tables to me
From: Doctor Schwa
Subject: Re: I don't understand functions and function tables
One way to think of a function is as a rule. You give it some object,
and it replies with some other object. For example, a catalog for a
shirt company might have a function called price, and price of green
shirt = $8 could be written as
price(green shirt) = 8
and we might also have
price(white shirt) = 6
and price(yellow shirt) = 8
and price(tie-dye shirt) = 12
and so on.
In math, functions are usually rules that work with numbers. The
object you give is a number, and the reply is another number. For
instance, the function rule might be "add two," and if we name that
function f,
f(4) = 6
f(5) = 7
and so on.
In general we could write f(x) = x+2.
Now, if you want to make a function table, you take a rule, say
g(x) = x^2, and make a table like this:
x | g(x)
---+-----
-2 | 4
-1 | 1
0 | 0
1 | 1
2 | 4
and so on. You could continue the table as long as you want to.
I hope this helps clear things up for you! If you have more questions
about functions, please do write back.
- Doctor Schwa, The Math Forum