1. Chapter 4.8: Determine if the Relation is a Function

2. Lesson 4.8: Function & Relations Definition Function: A rule that establishes a relationship between 2 quantities, the input and the output. Domain: x values Range: y values Input: x values Output: y values Set Notation {1,2,3} Only write the number once, even if it repeats Relation: Any set of ordered pairs For every x there is exactly one y

3. Lesson 4.8: Determining if the relation is a function To determine if a given relation is a function, we use the vertical line test. If the vertical line intersects the relation at one point as it moves across the graph, then that graph is a function. If the vertical line intersects the relation at more than one point as it moves across the graph, then that graph is NOT a function.

4. Lesson 4.8: Determining if the relation is a function- Vertical Line Test x y Run a vertical line across the page from left to right Since the line only touched once, there is only one x value for every y, it is a function.

5. Lesson 4.8: Determining if the relation is a function- Vertical Line Test x y Run a vertical line across the page from left to right Since the line touched more than once, there is more than one x value for every y, it is a function.

6. Lesson 4.8: Determining if the relation is a function given a table of values Step 1: Graph each point Step 2: Conduct vertical line test. 12341234 134134 Input Output x y 1 1 2 3 33 4 4 Domain: Range: {1,2,3,4} {1,3,4}

7. Lesson 4.8: Determining if the relation is a function given a table of values x y Step 1: Graph each point 12341234 134134 Input Output Step 2: Vertical Line Test Since the line only touched once, there is only one x value for every y, it is a function.

8. Lesson 4.8: Determining if the relation is a function given a table of values x y Step 1: Graph each point 4 134134 Input Output Step 2: Vertical Line Test Since the line touched more than once, there is more than one x value for every y, it is a function.

9. Lesson 4.8: Determining if the relation is a function given a table of values Input Output 12341234 134134 Input Output 4 134134