Functions F.IF.1 Understand that a function from one set (called the domain) to another set (called the range) assigns to each element of the domain exactly one element of the range. If f is a function and x is an element of its domain, then f(x) denotes the output of f corresponding to the input x. The graph of f is the graph of the equation y=f(x). F.IF.2 Use function notation, evaluate functions for inputs in their domains, and interpret statements that use function notation in terms of a context. SWBAT identify whether a relation is a function by looking at a graph, table of values, or an equation. SWBAT use function notation to evaluate the output of a function given a particular input. SWBAT identify the domain and range for a set of values.

Important Vocabulary Relation – Any set of input that has an output Function – Is a relation that every single input has exactly one output Input (x-coordinates) is also called the Domain Output (y-coordinates) is also called the Range Include these as important vocabulary words too!

Determining if a Relation is a Function If we are looking at a table of values, each input must have EXACTLY ONE output. If we are looking at a graph of values, we must use the vertical line test. No vertical line can pass through TWO OR MORE points on the graph.

Example 1 Does this relationship represent a function? Yes, no, why? If it is a function, what is the domain and range?

Example 2 Does this relationship represent a function? Yes, no, why? If it is a function, what is the domain and range?

Example 3 Do the relationships represent functions? If it is a function, what is the domain and range?

Guided Practice!

Is it a function? (3,2) (4,3) (5,4) (6,5)

Is it function?

Is it function?

Is it a function?

It is a function?

Independent Practice!

Using Function Notation! Function notation is A WAY TO NAME A FUNCTION. It is pronounced “f of x” . f(x) is a fancy way of writing “y” in an equation.

Example 1 Evaluate f(x) = x2 – 2x + 3 when X = -3 and X =4

Guided Practice 1 Evaluate for when x = 3, x = 0 and x = -2 f(x) = 2x - 5

Finish Guided Practice!

Independent Practice

Challenge! Name the function!

Exit Ticket (5 minutes) 1. Are the following relations functions? Yes or No? If so, state the domain and range! 2. Evaluate the function f(x) = 3x3 – 2x + 4 for when x = - 2 and when x = 2