SAT II Math II : Functions and Graphs

Study concepts, example questions & explanations for SAT II Math II

varsity tutors app store varsity tutors android store

Example Questions

Example Question #1 : Solving Quadratic Functions

A baseball is thrown straight up with an initial speed of 60 feet per second by a man standing on the roof of a 100-foot high building. The height of the baseball in feet as a function of time   in seconds is modeled by the function

To the nearest tenth of a second, how long does it take for the baseball to hit the ground?

Possible Answers:

Correct answer:

Explanation:

When the baseball hits the ground, the height is 0, so we set . and solve for .

This can be done using the quadratic formula:

Set :

One possible solution:

 

We throw this out, since time must be positive.

The other:

This solution, we keep. The baseball hits the ground in 5 seconds.

 

Example Question #1 : Solving Trigonometric Functions

Give the period of the graph of the equation

Possible Answers:

The correct answer is not among the other choices.

Correct answer:

The correct answer is not among the other choices.

Explanation:

The period of the graph of a sine function  is , or .

Since ,

.

This answer is not among the given choices.

Example Question #2 : Solving Trigonometric Functions

If , what must  be?

Possible Answers:

Correct answer:

Explanation:

Evaluate each trig function at the specified angle.

Replace the terms into the function.

Combine like-terms.

The answer is:  

Example Question #1 : Solving Piecewise And Recusive Functions

Define  and  as follows:

Evaluate .

Possible Answers:

Correct answer:

Explanation:

 by definition.

 

 on the set , so 

.

 on the set , so

.

Example Question #2 : Solving Piecewise And Recusive Functions

Define function  as follows:

Give the range of .

Possible Answers:

Correct answer:

Explanation:

The range of a piecewise function is the union of the ranges of the individual pieces, so we examine both of these pieces.

If , then . To find the range of  on the interval , we note:

The range of this portion of  is .

 

If , then . To find the range of  on the interval , we note:

The range of this portion of  is 

 

The union of these two sets is , so this is the range of  over its entire domain.

Example Question #1 : Solving Piecewise And Recusive Functions

Define function  as follows:

Give the range of .

Possible Answers:

Correct answer:

Explanation:

The range of a piecewise function is the union of the ranges of the individual pieces, so we examine both of these pieces.

 

If , then 

To find the range of  on the interval , we note:

The range of  on  is .

 

If , then 

To find the range of  on the interval , we note:

The range of  on  is .

 

The range of  on its entire domain is the union of these sets, or .

Example Question #1 : Solving Piecewise And Recusive Functions

Define functions  and  as follows:

Evaluate .

Possible Answers:

Undefined

Correct answer:

Explanation:

First, we evaluate  . Since , the definition of  for  is used, and 

Since 

, then

Example Question #5 : Solving Piecewise And Recusive Functions

Define functions  and  as follows:

Evaluate Evaluate .

Possible Answers:

Undefined

Correct answer:

Undefined

Explanation:

First, evaluate  using the definition of  for :

Therefore, 

However,  is not in the domain of 

Therefore,  is an undefined quantity.

Example Question #6 : Solving Piecewise And Recusive Functions

Define functions  and  as follows:

Evaluate .

Possible Answers:

Undefined

Correct answer:

Explanation:

First, evaluate  using the definition of  for :

Therefore, 

Evaluate  using the definition of  for :

Example Question #2 : Solving Piecewise And Recusive Functions

Define functions  and  as follows:

Evaluate .

Possible Answers:

Undefined

Correct answer:

Explanation:

First we evaluate . Since , we use the definition of  for the values in the range :

Therefore, 

Since , we use the definition of  for the range :

Learning Tools by Varsity Tutors