All SAT II Math II Resources
Example Questions
Example Question #1 : Graphing Piecewise And Recusive Functions
Define a function as follows:
How many -intercept(s) does the graph of
have?
Two
One
Three
Four
None
None
To find the -coordinates of possible
-intercepts, set each of the expressions in the definition equal to 0, making sure that the solution is on the interval on which
is so defined.
on the interval
or
However, neither value is in the interval , so neither is an
-intercept.
on the interval
However, this value is not in the interval , so this is not an
-intercept.
on the interval
However, this value is not in the interval , so this is not an
-intercept.
on the interval
However, neither value is in the interval , so neither is an
-intercept.
The graph of has no
-intercepts.
Example Question #2 : Graphing Piecewise And Recusive Functions
Define a function as follows:
How many -intercept(s) does the graph of
have?
Four
One
Two
Three
None
Two
To find the -coordinates of possible
-intercepts, set each of the expressions in the definition equal to 0, making sure that the solution is on the interval on which
is so defined.
on the interval
However, this value is not in the interval , so this is not an
-intercept.
on the interval
or
is on the interval
, so
is an
-intercept.
on the interval
is on the interval
, so
is an
-intercept.
on the interval
However, this value is not in the interval , so this is not an
-intercept.
The graph has two -intercepts,
and
.
Example Question #3 : Graphing Piecewise And Recusive Functions
Define function as follows:
Give the -intercept of the graph of the function.
The graph does not have a -intercept.
To find the -intercept, evaluate
using the definition of
on the interval that includes the value 0. Since
on the interval ,
evaluate:
The -intercept is
.
Example Question #4 : Graphing Piecewise And Recusive Functions
Define a function as follows:
At which of the following values of is
discontinuous?
I)
II)
III)
II and III only
None of I, II, and III
I and III only
I and II only
All of I, II, and III
I and III only
To determine whether is continuous at
, we examine the definitions of
on both sides of
, and evaluate both for
:
evaluated for
:
evaluated for
:
Since the values do not coincide, is discontinuous at
.
We do the same thing with the other two boundary values 0 and .
evaluated for
:
evaluated for
:
Since the values coincide, is continuous at
.
turns out to be undefined for
, (since
is undefined), so
is discontinuous at
.
The correct response is I and III only.
Example Question #5 : Graphing Piecewise And Recusive Functions
Define a function as follows:
At which of the following values of is the graph of
discontinuous?
I)
II)
III)
None of I, II, and III
I and II only
All of I, II, and III
I and III only
II and III only
II and III only
To determine whether is continuous at
, we examine the definitions of
on both sides of
, and evaluate both for
:
evaluated for
:
evaluated for
:
Since the values coincide, the graph of is continuous at
.
We do the same thing with the other two boundary values 0 and 1:
evaluated for
:
evaluated for
:
Since the values do not coincide, the graph of is discontinuous at
.
evaluated for
:
evaluate for
:
Since the values do not coincide, the graph of is discontinuous at
.
II and III only is the correct response.
Example Question #2 : Graphing Piecewise And Recusive Functions
Define a function as follows:
Give the -intercept of the graph of the function.
The graph does not have a -intercept.
To find the -intercept, evaluate
using the definition of
on the interval that includes the value 0. Since
on the interval ,
evaluate:
The -intercept is
.
All SAT II Math II Resources
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