Function Notation and Finding Function Values (3.6.3)

Question 1

• Function notationreplaces the “y =” in an equation with “f(x) =” which shows that each y-value depends on the value used
for x.

Answer 1

• Function notationreplaces the “y =” in an equation with “f(x) =” which shows that each y-value depends on the value used
for x.

Question 2

• f(x) shows the y-value for the given x and shows that the y-value can be found when an x-value is known and used in the
equation. Other letters are frequently used as well, so that you may find g(x), h(x), and so on.

Answer 2

• f(x) shows the y-value for the given x and shows that the y-value can be found when an x-value is known and used in the
equation. Other letters are frequently used as well, so that you may find g(x), h(x), and so on.

Question 3

• f(x) is read “f of x.” The expression f (2) is read as “f of 2”. f (2) indicates the value that y has in this function when x = 2

Answer 3

• f(x) is read “f of x.” The expression f (2) is read as “f of 2”. f (2) indicates the value that y has in this function when x = 2

Question 4

For this function, f (2) means to substitute 2 in each place
that you find an x in the expression. Then solve for the value
of the expression to determine f (2). f (2) is the y-value for
the point where x = 2 in this expression. Since this f (2) = 7,
on a graph, you would find the point (2, 7).
This notation replaces the old “y =” notation.
This f (1) uses 1 for every x to determine that f (1), or y, equals
1. On a graph this is the point (1, 1).
Now f (0) replaces x with 0 and it turns out that f (0) equals
–1. On a graph this is the point (0, –1).
For this function, g(2) equals 1/5. On a graph, this is the
point (2, 1/5)
For this function, h(2) equals . On a graph, this is the
point (2, ).

Answer 4

For this function, f (2) means to substitute 2 in each place
that you find an x in the expression. Then solve for the value
of the expression to determine f (2). f (2) is the y-value for
the point where x = 2 in this expression. Since this f (2) = 7,
on a graph, you would find the point (2, 7).
This notation replaces the old “y =” notation.
This f (1) uses 1 for every x to determine that f (1), or y, equals
1. On a graph this is the point (1, 1).
Now f (0) replaces x with 0 and it turns out that f (0) equals
–1. On a graph this is the point (0, –1).
For this function, g(2) equals 1/5. On a graph, this is the
point (2, 1/5)
For this function, h(2) equals . On a graph, this is the
point (2, ).