1 7 b Functions Which ones are Functions

1 -7 b Functions

Which ones are Functions? Domain Range Le. Bron James Los Angeles Lakers FSU SEC Kobe Bryant Oklahoma City Thunder UF ACC Kevin Durant Cleveland Cavaliers Miami Rule: Who Plays for who? Rule: Who Plays where? Domain Range Kim Kardashian Kanye West Kirsten Stewart Edward Cullen Reggie Bush Rule: Who dated who?

• Function – a relation in which each element of the domain is paired with exactly one element of the range. (the xvalues CANNOT repeat!)

Vertical Line Test – used to see if a graph represents a function • If no vertical line can be drawn so that it intersects the graph more than once, then the graph is a function. • If a vertical line can be drawn so that it intersects the graph at two or more points then the relation is NOT a function.

Is it a function? Ex 4 Ex 5

Is it a function? Ex 6 Ex 7

Is it a function? Ex 8 Ex 9

Function Notation Equation y = 3 x – 8 Function Notation f(x) = 3 x – 8 x represents the elements of the domain. f(x) represents the elements of the range. If you want to find the value in the range that corresponds to the element 5 in the domain you would write f(5) “f of 5”. The value f(5) is found by substituting 5 for x in the equation.

If f(x) = 3 x – 4 find: • Ex 8 f(4) • Ex 9 f(-5) • Ex 10 f(2 – x)

If h(x) = x 2 + 5 find: • Ex 11 h(-3) • Ex 12 h(6 y) • Ex 13 4[h(w)]

Homework Pg 49 -50 #’s 3, 5 -8, 11 -19, 34, 35, 43