Relations, Functions, Domain and Range

Front

What is a function?

Back

A function is a relation where each input (x-value) is associated with exactly one output (y-value).

Front

Which relation is NOT a function? {(1,-5), (3,1), (-5,4), (4,-2)}, {(2,7), (3,7), (4,7), (5,8)}, {(1,-5), (-1,6), (1,5), (6,-3)}, {(3,-2), (5,-6), (7,7), (8,8)}

Back

{(1,-5), (-1,6), (1,5), (6,-3)}

Front

What are the x values or inputs of a relation called?

Back

Domain

Front

What are the y values or outputs of a relation called?

Back

Range

Front

Is the relation {(2,3), (3,4), (2,5)} a function?

Back

No, because the input 2 is associated with two different outputs (3 and 5).

Front

Write the domain for the relation {(-4, 3), (2, 1), (0, 3), (-3, -2)}

Back

xE{-4, -3, 0, 2}.

Front

Is the graph of a vertical line a function?

Back

No, because it fails the vertical line test.

Front

What is the vertical line test?

Back

A method to determine if a relation is a function; if a vertical line intersects the graph at more than one point, it is not a function.

Front

What is the range of the relation {(1,2), (2,3), (3,4)}?

Back

yE{2, 3, 4}.

Front

If a function is defined as f(x) = 2x + 3, what is f(2)?

Back

f(2) = 2(2) + 3 = 7.