This preview shows page 1. Sign up to view the full content.
Unformatted text preview: tion.
y (−2,4) All vertical lines
crosses this graph at
(2,4) only 1 point, so
every x-value will be
paired with a single
x y (4,2) x (4,−2) The vertical line crosses
the graph at 2 points, so
this is one x-value that
has 2 different y-values;
this is not a function. exercise: Which of the graphs shown at the bottom of the previous page are functions? Function Notation
f (x) is “f of x” or “the value of function f for any given value of the variable x”.
f is the name of this function; other letters or words can be used to name functions.
x is the variable that f depends on. Function notation can be used to define a function for a question.
exercise: f (x) = x2 − 4
exercise: f (3) = (3)2 − 4 = 5 In this example the value of the function f for a given value of x is
calculated by squaring the x-value and then subtracting 4.
f (0) = f (1) = f (−1) = f (2) = f (½) = The graph of y = f (x) would have points (3,5) , ____________________________________
and many others. Unit 1 – Day 2: Functions Review and Quadratic Functions Page 3 of 4 ZEROS OF FUNCTIONS
The zeros of a function are the x-values for which the function value is 0.
example: Determine the zero(s) of the function The zeros of f (x) are 2 and −2. f (x) = x2 − 4
0 = x2 − 4
4 = x2
x = 2 o r x = −2 Whe...
View Full Document