4.2.notebook
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4.2 Introduction to Functions
Are all rectangles squares?
Are all squares rectangles?
Relations and Functions are related in the
same way that rectangles and squares are.
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A function has each of its x-values
(domain) corresponding to exactly one yvalue (range).
So, all functions are relations, but not all
relations are functions!
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Which of these relations are functions?
3
1
2
2
­1
2
­1
3
4
3
­2
1
4
1
2
4
3
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Which one of these relations are functions?
{(4, 2), (­5, 4), (0, 0), (8, 4)}
{(­1, 6), (8, 9), (­1, 4), (­3, 10)}
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If you are given a GRAPH, the easiest
way to tell whether or not it's a
function is to use the VERTICAL LINE
TEST.
**Hint: Use your pencil/pen/finger as
the vertical line...
Examples on page 266 & 267 of book...
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Function Notation:
means the
same thing
as
is read "f of x" Nov 30­2:05 PM
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Evaluate the following function:
Given Find:
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Evaluate the following function:
Given Find:
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Some problems to try:
Page 273 # 5 - 58 down the column
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