Common Core: High School - Functions : High School: Functions

Study concepts, example questions & explanations for Common Core: High School - Functions

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All Common Core: High School - Functions Resources

6 Diagnostic Tests 82 Practice Tests Question of the Day Flashcards Learn by Concept

Example Questions

Example Question #5 : Function And Graph Relationships: Ccss.Math.Content.Hsf If.B.4

What is the end behavior of the following function?

Possible Answers:

Correct answer:

Explanation:

This question is testing one's ability to grasp the relationship between a function algebraically, and the image it creates graphically. Problems like these are considered modeling problems because of their application. For example, the intercepts, extreme values, slope, symmetry, and end behavior for these functions mark key relationships between the inputs and the resulting outputs. 

For the purpose of Common Core Standards, application of interpreting functions fall within the Cluster B of the function and use of function notation concept (CCSS.MATH.CONTENT.HSF-IF.B). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Identify what the question is asking.

This particular question is asking for the end behavior of the function. This means we will need to examine the graph of the function as the  values get larger and larger.

Step 2: Determine the approach to solve the problem.

      I. Graphically plot the function using computer technology or graphing calculator.

         Then, find the end behavior,  values as  the  values get larger and larger.

Screen shot 2016 01 11 at 10.22.33 am

Step 3: Interpret the above graph for the end behavior.

Looking at the graph above there appears to be a vertical asymptote and a horizontal asymptote. The vertical asymptote effects the behavior of the graph as the  values get close to zero. The horizontal asymptote effects the behavior of the graph as the  values gets closer to positive infinity and negative infinity. In other words the horizontal asymptote effects the end behavior of the function. As the  values get larger and larger the function values or end behavior of the function approaches zero.

Step 4: Verify the solution algebraically.

Using the algebraic technique, plug in larger values for  to see the trend in the function values.

As  since by definition, one divided by a large number becomes an extremely small number close to zero.

Step 5: Answer question.

Example Question #6 : Function And Graph Relationships: Ccss.Math.Content.Hsf If.B.4

What is the periodicity of the following function ?

Possible Answers:

Correct answer:

Explanation:

This question is testing one's ability to grasp the relationship between a function algebraically, and the image it creates graphically. Problems like these are considered modeling problems because of their application. For example, the intercepts, extreme values, slope, symmetry, and end behavior for these functions mark key relationships between the inputs and the resulting outputs. 

For the purpose of Common Core Standards, application of interpreting functions fall within the Cluster B of the function and use of function notation concept (CCSS.MATH.CONTENT.HSF-IF.B). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Identify what the question is asking.

This particular question is asking for the periodicity of the function

Step 2: Determine the approach to solve the problem.

      I. Graphically plot the function using computer technology or graphing calculator.

      II. Algebraically solve using the general formula,  where 

Step 3: Using option II, the algebraic method to solve for the periodicity of the given function.

Therefore the periodicity is 

.

Example Question #7 : Function And Graph Relationships: Ccss.Math.Content.Hsf If.B.4

Screen shot 2016 01 11 at 12.21.42 pm

Find the interval where  is decreasing.

Possible Answers:

Correct answer:

Explanation:

This question is testing one's ability to grasp the relationship between the image a function creates graphically and the intervals where the function is increase, decreasing, positive, or negative. Problems like these are considered modeling problems because of their application. For example, the intercepts, extreme values, slope, symmetry, and end behavior for these functions mark key relationships between the inputs and the resulting outputs. 

For the purpose of Common Core Standards, application of interpreting functions fall within the Cluster B of the function and use of function notation concept (CCSS.MATH.CONTENT.HSF-IF.B). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Identify what the question is asking.

This particular question is asking for where the function is decreasing. It is important to understand that when a function is decreasing, the graph exhibits a negative slope.

Step 2: Identify the intervals where the graph is negative (decreasing) and where it is positive (increasing).

Screen shot 2016 01 11 at 12.21.42 pm

Looking at the graph above, it is seen that  is negative or decreasing roughly between . Since the specific function is also included in the question we can use algebra along with the initial assumptions made using the graph to solve the problem.

Step 3: Use algebra to find the decreasing interval of the function.

Looking at the possible answer selections, there are only two possible selections that contain two negative  values.

Option 1: 

Option 2:

Lets convert the fractions into decimals.

Since  is closer to negative one the decreasing interval of the function is,

.

 

 

Example Question #8 : Function And Graph Relationships: Ccss.Math.Content.Hsf If.B.4

What is the relative minimum of the function .

Possible Answers:

Correct answer:

Explanation:

This question is testing one's ability to grasp the relationship between a function algebraically, and the image it creates graphically. Problems like these are considered modeling problems because of their application. For example, the intercepts, extreme values, slope, symmetry, and end behavior for these functions mark key relationships between the inputs and the resulting outputs. 

For the purpose of Common Core Standards, application of interpreting functions fall within the Cluster B of the function and use of function notation concept (CCSS.MATH.CONTENT.HSF-IF.B). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Identify what the question is asking.

This particular question is asking for the relative minimum of the function.

Step 2: Determine the approach to solve the problem.

      I. Graphically plot the function using computer technology or graphing calculator.

         Then, find where the graph reaches its valley.

Step 3: For the purpose of this question let's solve using graphing calculator technology.

Graphing the function results in the following graph.


Screen shot 2016 01 11 at 1.31.52 pm

Looking at the above graph the valley occurs roughly at the point .

Looking at the possible answer choices, there are only two options that contain a positive  and  value.

Option 1:

Option 2:

Since the  values are the same in these two points lets compare the  values.

 and 

Since 

 is closer to  that makes the valley of the function occur at the point, .

Example Question #9 : Function And Graph Relationships: Ccss.Math.Content.Hsf If.B.4

What is the relative maximum of the following function?

Possible Answers:

Correct answer:

Explanation:

This question is testing one's ability to grasp the relationship between a function algebraically, and the image it creates graphically. Problems like these are considered modeling problems because of their application. For example, the intercepts, extreme values, slope, symmetry, and end behavior for these functions mark key relationships between the inputs and the resulting outputs. 

For the purpose of Common Core Standards, application of interpreting functions fall within the Cluster B of the function and use of function notation concept (CCSS.MATH.CONTENT.HSF-IF.B). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Identify what the question is asking.

This particular question is asking for the relative maximum of the function.

Step 2: Determine the approach to solve the problem.

      I. Graphically plot the function using computer technology or graphing calculator.

         Then, find where the graph reaches its peak.

Step 3: For the purpose of this question let's solve using graphing calculator technology.

Graphing the function results in the following graph.

Screen shot 2016 01 11 at 9.20.29 am

Step 4: Trace the function using the graphing calculator to find the coordinates of the peak.

Screen shot 2016 01 11 at 9.18.12 am

Step 5: Answer the question.

The relative maximum of the function occurs at .

 

Example Question #10 : Function And Graph Relationships: Ccss.Math.Content.Hsf If.B.4

Given the following function, find the line of symmetry.

Possible Answers:

Correct answer:

Explanation:

This question is testing one's ability to grasp the relationship between a function algebraically, and the image it creates graphically. Problems like these are considered modeling problems because of their application. For example, the intercepts, extreme values, slope, symmetry, and end behavior for these functions mark key relationships between the inputs and the resulting outputs. 

For the purpose of Common Core Standards, application of interpreting functions fall within the Cluster B of the function and use of function notation concept (CCSS.MATH.CONTENT.HSF-IF.B). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Identify what the question is asking.

This particular question is asking for the axis of symmetry for this particular function.

Step 2: Determine the approach to solve the problem.

      I. Graphically plot the function using computer technology or graphing calculator.

         Then, find the vertical line that splits the graph into two mirrored images. In other words, find the vertical line that is equal to the  value of the vertex of the function.

Step 3: Graph the function and plot the vertical line that is equal to the  value of the vertex.

Screen shot 2016 01 11 at 1.57.24 pm

Step 4: Answer the question.

The vertex is located at the point  therefore, the axis of symmetry is at .

Example Question #41 : High School: Functions

Find the axis of symmetry for the following function.

Possible Answers:

Correct answer:

Explanation:

This question is testing one's ability to grasp the relationship between a function algebraically, and the image it creates graphically. Problems like these are considered modeling problems because of their application. For example, the intercepts, extreme values, slope, symmetry, and end behavior for these functions mark key relationships between the inputs and the resulting outputs. 

For the purpose of Common Core Standards, application of interpreting functions fall within the Cluster B of the function and use of function notation concept (CCSS.MATH.CONTENT.HSF-IF.B). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Identify what the question is asking.

This particular question is asking for the axis of symmetry for this particular function.

Step 2: Determine the approach to solve the problem.

      I. Graphically plot the function using computer technology or graphing calculator.

         Then, find the vertical line that splits the graph into two mirrored images. In other words, find the vertical line that represents a vertical asymptote and the horizontal line that represents a horizontal asymptotes.

Step 3: Graph the function and plot the vertical line that is equal to the  value of the vertical line that represents a vertical asymptote and the  value that is the horizontal line that represents a horizontal asymptotes.

Screen shot 2016 01 11 at 2.03.32 pm

Step 4: Answer the question.

The vertical asymptote occurs at   and the horizontal asymptote occurs at  thus making them both axis of symmetry for the given function.

Example Question #42 : High School: Functions

Given the function , what is the  intercept?

Possible Answers:

Correct answer:

Explanation:

This question is testing one's ability to grasp the relationship between a function algebraically, and the image it creates graphically. Problems like these are considered modeling problems because of their application. For example, the intercepts, extreme values, slope, symmetry, and end behavior for these functions mark key relationships between the inputs and the resulting outputs. 

For the purpose of Common Core Standards, application of interpreting functions fall within the Cluster B of the function and use of function notation concept (CCSS.MATH.CONTENT.HSF-IF.B). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Identify what the question is asking.

This particular question is asking for the  intercept of the function.

Step 2: Determine the approach to solve the problem.

      I. Graphically plot the function using computer technology or graphing calculator.

         Then, find where the graph intersects the -axis.

     II. Algebraically, find the intercepts by substituting in zero for  and solving for  (calculating the -intercept).

Step 3: Choose an approach from Step 2 and perform the necessary actions.

For the purpose of this question let's solve using option I.

Screen shot 2016 01 12 at 10.27.05 am

Looking at the graph above, the function crosses the -axis at twelve. Therefore, the -intercept is 12.

Example Question #1 : Graph's Domain: Ccss.Math.Content.Hsf If.B.5

A vehicle increases its speed by  miles per hour every five minutes for two hours resulting in a maximum speed of 95 miles per hour. If  represents this function, what is the domain of
Possible Answers:

Correct answer:
Explanation:
This particular question is testings one's ability to recognize characteristics of a function in terms of its context. Specifically, it is testing the ability to identify the domain of a function, or in other words, the possible input values that logically and mathematically work for the situation that is described by .
 

For the purpose of Common Core Standards, "relate the domain of a function to its graph and, where applicable, to the quantitative relationship it describes" falls within the Cluster B of "interpret functions that arise in applications in terms of the context" concept (CCSS.MATH.CONTENT.HSF-IF.B.5). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Identify what the question is asking for.
This question is asking to find the domain, possible x values that make sense for this situation .
 
Step 2: Use the information that describes  and create a graph that could possibly fit.
Let us identify the known information of the function.
 
 is in intervals of "miles per every five minutes" and goes from zero to two hours. Therefore to find the units that the -axis will have, convert two hours into minutes and then into intervals of five minutes.
 
 
 
The maximum speed is 95 miles per hour. Therefore, the -axis spans from zero to 95.
At some value  the function reaches a maximum value of,
 
 .
 
Since the question states, "A vehicle increases its speed by  miles per hour every five minutes for two hours", a linear relationship being time and speed is assumed.
 
Using the known information creates the graph below.

Screen shot 2016 01 12 at 12.40.02 pm
Step 3: Using the graph above, identify the domain.
Screen shot 2016 01 12 at 12.40.02 pm
Recalling that the domain of a function is the interval of  values that result in a real output that lies in the range of the function. In the above graph the red line indicates the domain of the function. In mathematical terms,
 
.

Example Question #2 : Graph's Domain: Ccss.Math.Content.Hsf If.B.5

Q8

A vehicle starts to increase its speed after 25 minutes at a rate of   miles per hour every five minutes for 125 minutes resulting in a maximum speed of 35 miles per hour. If  represents this function, what is the domain of 

Possible Answers:

Correct answer:

Explanation:
This particular question is testings one's ability to recognize characteristics of a function in terms of its context. Specifically, it is testing the ability to identify the domain of a function, or in other words, the possible input values that logically and mathematically work for the situation that is described by .
 

For the purpose of Common Core Standards, "relate the domain of a function to its graph and, where applicable, to the quantitative relationship it describes" falls within the Cluster B of "interpret functions that arise in applications in terms of the context" concept (CCSS.MATH.CONTENT.HSF-IF.B.5). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Identify what the question is asking for.
This question is asking to find the domain, possible x values that make sense for this situation .
 
Step 2: Use the information that describes  and create a graph that could possibly fit.
Let us identify the known information of the function.
 
 is in intervals of "miles per every five minutes" and goes from zero to 125 minutes. Therefore to find the units that the -axis will have, convert 125 minutes into intervals of five minutes.
 
 
 
Since the question states, "A vehicle starts to increase its speed after 25 minutes at a rate of  miles per hour every five minutes for 125 minutes", a linear relationship being time and speed is assumed.
 
Using the known information creates the graph below.

Q8

Step 3: Using the graph above, identify the domain.
 
Recalling that the domain of a function is the interval of  values that result in a real output that lies in the range of the function. In mathematical terms,
 
.

All Common Core: High School - Functions Resources

6 Diagnostic Tests 82 Practice Tests Question of the Day Flashcards Learn by Concept
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