Algebra II: Functions
Terms
Domain
-
The set of all inputs of a relation or function.
Function
-
A relation in which each input has only one output. Often denoted
f (x)
.
Horizontal Line Test
-
If every horizontal line you can draw passes through only 1 point,
x
is a
function of
y
. If you can draw a horizontal line that passes through 2
points,
x
is not a function of
y
.
Range
-
The set of all outputs of a relation or function.
Relation
-
A set of inputs and outputs, often written as ordered pairs (input, output).
Restricted Domain
-
The domain of a function that is not defined for all real numbers.
Vertical Line Test
-
If every vertical line you can draw goes through only 1 point,
y
is a function
of
x
. If you can draw a vertical line that goes through 2 points,
y
is not
a function of
x
.





