Key Features of Functions

Function Key Features

Algebra Unit 3
Lesson 3.2

Key Features

on a Graph

Intervals of

increase, decrease and constant

X- and Y-Intercepts

Minimum and Maximum

Intervals of positive and negative

Intervals

When x values go up..

• Increasing: Y values go UP

• Decreasing: Y values goes DOWN

• Constant: Y values stay the SAME

Multiple Choice

Which domain describes the INCREASING interval?

• 0 < x < 2

• 2 < x < 4

• 8 < x < 10

Multiple Choice

Which domain describes the DECREASING interval?

• 0 < x < 2

• 2 < x < 4

• 8 < x < 10

Multiple Choice

Which domain describes the CONSTANT interval?

• 0 < x < 2

• 2 < x < 4

• 8 < x < 10

Intercepts

• X-intercepts are where the graph touches the X-axis

• Y-intercepts are where the graph touches the Y-axis

Multiple Select

Which of these are x-intercepts?

• ( 0 , 2 )

• ( 2 , 0 )

• ( -6 , 0 )

• ( 0 , 0 )

• ( 0, -6 )

Multiple Choice

How many y-intercepts does this graph have?

• 0

• 1

• 2

• 3

• Infinite

Minimums and Maximums

• Maximum is the highest point on the graph and is written as an ordered pair (6, 8)

• Minimum is the lowest point on the graph and is written as an ordered pair ( 0, 0 ) and ( 10 , 0 )

Fill in the Blank

Where is this function positive?

>

Fill in the Blank

Where is this function negative?

<

Relation or Function?

• Both have sets of ORDERED PAIRS

• Both have INPUTS and OUTPUTS

• Only FUNCTIONS have exactly one output for each input

• Use the VERTICAL LINE TEST to see if a graph is a function.

• Each x-value (INPUTS) only occurs once. The x-values DO NOT repeat.

Multiple Choice

Is this mapping a function?

• YES

• NO

Multiple Select

Pick the graphs that are functions.

• A

• B

• C

Multiple Choice

Which set of ordered pairs is not a function?

• 1

• 2

• 3

• 4