Notes from a PPT: Functions vs. Relations / Domain & Range Coordinate Algebra Agenda: Notes from a PPT: Functions vs. Relations / Domain & Range Learning Target: Students can define a relation and explain the difference between a relation and a function. Students can determine the domain and range of relations and functions. Standard: MCC9-12.F.IF.1 and 2
Functions vs. Relations
Relation A relation is simply a set of ordered pairs. The set of all first values (x- values) is the domain. The set of all second values (y-values) is the range.
Function A relation where EACH input has exactly ONE output Each element from the domain is paired with one and only one element from the range
Domain x – coordinates Independent variable Input
Range y – coordinates Dependent variable Output
How do I know it’s a function? Look at the input and output table – Each input must have exactly one output. Look at the Graph – The Vertical Line test: NO vertical line can pass through two or more points on the graph
function Example 1: {(3, 2), (4, 3), (5, 4), (6, 5)} Is the following relation a function? Example 1: {(3, 2), (4, 3), (5, 4), (6, 5)} function
Is the following relation a function? Example 2: function
Is the following relation a function? Example 3: relation
function Is the following relation a function? Example 4: ( x, y) = (student’s name, shirt color) function
Is the following relation a function? Example 5: Red Graph relation
function Is the following relation a function? Jacob Angela Nick Honda Example 6 Jacob Angela Nick Greg Tayla Trevor Honda Toyota Ford function
function A person’s cell phone number versus their name. Is the following relation a function? Example 7 A person’s cell phone number versus their name. function
Only list repeated values once Put in order from least to greatest Domain and Range Only list repeated values once Put in order from least to greatest
What are the Domain and Range? {1, 2, 3, 4, 5, 6} {1, 3, 6, 10, 15, 21}
What are the Domain and Range? {0, 1, 2, 3, 4} {1, 2, 4, 8, 16}
What are the Domain and Range? All Reals All Reals
What are the Domain and Range? x ≥ -1 All Reals
Functions Practice worksheet Homework Functions Practice worksheet