Transcript Sect. 5-3: Functions, Tables, and Graphs

5-3 Functions, Tables, and Graphs
Sect. 5-3: Functions, Tables,
and Graphs
January 17th, 2013
5-3 Functions, Tables, and Graphs
• A function operates according
to a rule to produce exactly
one output value for each input
value.
• The input is the value
substituted into the function.
• The output is the value you
get from a specific input.
5-3 Functions, Tables, and Graphs
One variable represents the input, and the
other represents the output.
Rule
Output
Input
You can use a table to organize and display the
input and output values of a function.
5-3 Functions, Tables, and Graphs
Find the output for each input.
y = 8x + 5
Input
Rule
Output
x
8x + 5
y
–4
–2
1
5-3 Functions, Tables, and Graphs
Find the output for each input.
y = 4x2
Input
Rule
Output
x
4x2
y
–3
0
4
5-3 Functions, Tables, and Graphs
Your Turn!
Find the output for each input.
y = 5x + 3
Input
Rule
Output
x
5x + 3
y
–6
–3
3
5-3 Functions, Tables, and Graphs
Your Turn!
Find the output for each input.
y = 3x2
Input
Rule
Output
x
3x2
y
–2
0
5
5-3 Functions, Tables, and Graphs
You can also use a graph to represent a
function. The corresponding input and
output values together form unique
ordered pairs.
Remember!
An ordered pair is a pair of numbers that
represents a point on a graph.
5-3 Functions, Tables, and Graphs
Helpful Hint
When writing an ordered pair, write the input
value first and then the output value. (x,y)
5-3 Functions, Tables, and Graphs
Make a function table for x = –2, –1, 0, 1, and 2, and
graph the resulting ordered pairs.
y = 3x – 4
Input
x
Rule
3x – 4
4
Output
Ordered
Pair
y
(x, y)
2
–4 –2
–2
–2
–1
–4
0
1
2
y
–6
–8
–10
2
4
x
5-3 Functions, Tables, and Graphs
Make a function table for x = –2, –1, 0, 1, and 2, and
graph the resulting ordered pairs.
y
y = 5x2
20
Input
Rule
x
5x2
Output
y
Ordered
Pair
16
(x, y)
12
–2
8
–1
4
0
1
2
–8
–4 O
4
8
x