Function, describes a correlation or coincidence between a dependent variable (Y Y ) and an independent variable (X X ). The legitimacy of this relationship between the variables is called the " correspondence rule ".

Verbal representation of a function

The verbal representation of a function expresses the connection between variables verbally, i.e. through a story.

A typical verbal representation of a function can look like this:

  • Assuming that Daniel reads all the books he buys that month, the total number of books Daniel reads per year (Y Y ) is a function of the number of books Danny buys each month (X X ).

Tabular representation of a function

A tabular representation of a function is a demonstration of the legitimacy of a function using a table of values X X (independent variable) and the corresponding values Y Y (dependent variable).

In general, a table of values is shown as follows:

A1 - Verbal representation of a new function

Practice Representing a Function Verbally and with Tables

Examples with solutions for Representing a Function Verbally and with Tables

Exercise #1

Determine whether the given graph is a function?

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Video Solution

Step-by-Step Solution

It is important to remember that a function is an equation that assigns to each element in domain X one and only one element in range Y

We should note that for every X value found on the graph, there is one and only one corresponding Y value.

Therefore, the graph is indeed a function.

Answer

Yes

Exercise #2

Is the given graph a function?

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Video Solution

Step-by-Step Solution

It is important to remember that a function is an equation that assigns to each element in domain X one and only one element in range Y

Let's note that in the graph:

f(0)=2,f(0)=2 f(0)=2,f(0)=-2

In other words, there are two values for the same number.

Therefore, the graph is not a function.

Answer

No

Exercise #3

Does the graph below represent a function?

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Video Solution

Step-by-Step Solution

It is important to remember that a function is an equation that assigns to each value in domain x x only one value in range y y .

Since we can see that for every x x value found on the graph there is only one correspondingy y value, the graph is indeed a function.

Answer

Yes

Exercise #4

Determine whether the following table represents a function

XY-1015811

Video Solution

Step-by-Step Solution

It is important to remember that a constant function describes a situation where as the X value increases, the function value (Y) remains constant.

In the table, we can observe that there is a constant change in X values, meaning an increase of 1, and a constant change in Y values, meaning an increase of 3

Therefore, according to the rule, the table describes a function.

Answer

Yes

Exercise #5

Determine whether the following table represents a constant function:

XY02468-3-3-3-3-3

Video Solution

Step-by-Step Solution

It is important to remember that a constant function describes a situation where, as the X value increases, the Y value remains constant.

In the table, we can see that there is a constant change in the X values, specifically an increase of 2, while the Y value remains constant.

Therefore, the table does indeed describe a constant function.

Answer

Yes, it does

Exercise #6

Determine whether the data in the following table represent a constant function

XY012348

Video Solution

Step-by-Step Solution

It is important to remember that a constant function describes a situation where as the X value increases, the function value (Y) remains constant.

In the table, we can observe that there is a constant change in X values, meaning an increase of 1, and a non-constant change in Y values - sometimes increasing by 1 and sometimes by 4

Therefore, according to the rule, the table does not describe a function

Answer

No

Exercise #7

Determine whether the following table represents a constant function

XY-101247

Video Solution

Step-by-Step Solution

To determine if the table represents a constant function, we need to examine the Y-values corresponding to the X-values given in the table.

  • Step 1: Identify the given values from the table. The pairs are as follows: - For X=1X = -1, Y=2Y = 2 - For X=0X = 0, Y=4Y = 4 - For X=1X = 1, Y=7Y = 7
  • Step 2: Check if all Y-values are the same. Compare Y-values for each X-value:
  • - Y=2Y = 2 when X=1X = -1, - Y=4Y = 4 when X=0X = 0, - Y=7Y = 7 when X=1X = 1.

Since the Y-values (2, 4, and 7) are not the same, the function is not constant.

Thus, the table does not represent a constant function. The correct choice is: No.

Answer

No

Exercise #8

Determine whether the following table represents a function

XY-226101416111621

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify the given pairs of (X,Y)(X, Y).
  • Step 2: Verify that each XX maps to exactly one YY.
  • Step 3: Conclude whether the table represents a function.

Now, let's work through each step:
Step 1: The pairs given are: (2,1)(-2, 1), (2,6)(2, 6), (6,11)(6, 11), (10,16)(10, 16), (14,21)(14, 21).

Step 2: For each input value XX, we check its corresponding output YY:

  • X=2X = -2 maps to Y=1Y = 1
  • X=2X = 2 maps to Y=6Y = 6
  • X=6X = 6 maps to Y=11Y = 11
  • X=10X = 10 maps to Y=16Y = 16
  • X=14X = 14 maps to Y=21Y = 21
None of the values of XX is associated with more than one different YY value.

Step 3: Since each XX value has exactly one corresponding YY value, the table represents a function.

Yes

Answer

Yes

Exercise #9

Is the given graph a function?

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Video Solution

Step-by-Step Solution

To determine if the given graph represents a function, we use the vertical line test: if any vertical line intersects the graph at more than one point, the graph is not a function.

Let's apply this test to the graph:

  • Examine different sections of the graph by drawing imaginary vertical lines.
  • Look for intersections where more than one point exists on the vertical line.

Upon examining the graph, we observe that there are several vertical lines that intersect the graph at multiple points, particularly in areas with loops or overlapping curves. This indicates that at those x x -values, there are multiple y y -values corresponding to them.

Since there exist such vertical lines, according to the vertical line test, the graph does not represent a function.

Thus, the solution to this problem is that the given graph is not a function.

Answer

No

Exercise #10

Is the given graph a function?

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Video Solution

Step-by-Step Solution

To determine if the graph in question represents a function, we'll employ the Vertical Line Test. This test helps to ascertain whether each input value from the domain (x-values) is connected to a unique output value (y-values).

  • According to the Vertical Line Test, a graph represents a function if no vertical line can intersect the graph at more than one point.
  • In the provided diagram, the graph is a straight line.
  • Visual inspection shows that any vertical line drawn at any point along the x-axis intersects the line exactly once.
  • This indicates that for each x-value, there is a unique corresponding y-value. Therefore, the relationship depicted by the graph meets the criteria for a function.

Thus, the given graph correctly characterizes a function.
Therefore, the solution to the problem is Yes.

Answer

Yes

Exercise #11

Is the given graph a function?

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Video Solution

Step-by-Step Solution

To determine whether the graph represents a function, we apply the Vertical Line Test. Here are the steps we follow:

  • Step 1: Visualize placing a vertical line across various parts of the graph.
  • Step 2: Check if the vertical line intersects the graph at more than one point at any given position.

Step 1: On evaluating the given graph carefully, there is a notable presence of a vertical line passing through multiple y-values. Specifically, the vertical line goes from y=3 y = -3 to y=3 y = 3 at x=3 x = 3 .

Step 2: Since this vertical line at x=3 x = 3 intersects the graph at an infinite number of points, it fails the Vertical Line Test.

Therefore, the graph does not represent a function. According to our analysis and the Vertical Line Test, the correct answer is No.

Answer

No

Exercise #12

Is the given graph a function?

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Video Solution

Step-by-Step Solution

To determine if the graph is a function, we will use the Vertical Line Test.

The Vertical Line Test states that a graph represents a function if and only if no vertical line intersects the graph at more than one point.

Let's apply this test to the given graph, where a horizontal line is drawn. This line represents the function the graph should be verified against.

  • Step 1: Conceptualize vertical lines passing through different x-values across the domain of the graph.
  • Step 2: Observe if any of these vertical lines intersect the graph at more than one point.

Upon inspection of the graph, we see that every vertical line intersects the graph at exactly one point.

This indicates that for every input (x-value), there is a unique output (y-value), fulfilling the criteria for the definition of a function.

Therefore, according to the Vertical Line Test, the given graph is indeed a function.

The correct choice is: Yes

Answer

Yes

Exercise #13

Which of the following equations corresponds to the function represented in the graph?

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Video Solution

Step-by-Step Solution

Let's use the below formula in order to find the slope:

m=y2y1x2x1 m=\frac{y_2-y_1}{x_2-x_1}

We begin by inserting the known data from the graph into the formula:

(0,2),(2,0) (0,-2),(-2,0)

m=200(2)= m=\frac{-2-0}{0-(-2)}=

20+2= \frac{-2}{0+2}=

22=1 \frac{-2}{2}=-1

We then substitute the point and slope into the line equation:

y=mx+b y=mx+b

0=1×(2)+b 0=-1\times(-2)+b

0=2+b 0=2+b

Lastly we combine the like terms:

0+(2)=b 0+(-2)=b

2=b -2=b

Therefore, the equation will be:

y=x2 y=-x-2

Answer

y=x2 y=-x-2

Exercise #14

Which of the following equations corresponds to the function represented in the table?

XY-3-1135246810

Video Solution

Step-by-Step Solution

We will begin by using the formula for finding slope:

m=y2y1x2x1 m=\frac{y_2-y_1}{x_2-x_1}

First let's take the points:

(1,4),(3,8) (-1,4),(3,8)

m=843(1)= m=\frac{8-4}{3-(-1)}=

843+1= \frac{8-4}{3+1}=

44=1 \frac{4}{4}=1

Next we'll substitute the point and slope into the line equation:

y=mx+b y=mx+b

8=1×3+b 8=1\times3+b

8=3+b 8=3+b

Lastly we'll combine like terms:

83=b 8-3=b

5=b 5=b

Therefore, the equation will be:

y=x+5 y=x+5

Answer

y=x+5 y=x+5

Exercise #15

Which of the following equations corresponds to the function represented in the table?

XY-125811246810

Video Solution

Step-by-Step Solution

To determine which equation corresponds to the function given by the table, we will test each equation using the (x,y) (x, y) pairs from the table. Specifically, we will verify which equation satisfies all pairs so that we can conclude it functions as desired.

Consider the equation y=23x+223 y = \frac{2}{3}x + 2\frac{2}{3} .

  • For x=1 x = -1 :

Substitute into the equation:
y=23(1)+223=23+83=63=2 y = \frac{2}{3}(-1) + 2\frac{2}{3} = -\frac{2}{3} + \frac{8}{3} = \frac{6}{3} = 2 . The value matches the table, y=2 y = 2 .

  • For x=2 x = 2 :

Substitute into the equation:
y=23(2)+223=43+83=123=4 y = \frac{2}{3}(2) + 2\frac{2}{3} = \frac{4}{3} + \frac{8}{3} = \frac{12}{3} = 4 . The value matches the table, y=4 y = 4 .

  • For x=5 x = 5 :

Substitute into the equation:
y=23(5)+223=103+83=183=6 y = \frac{2}{3}(5) + 2\frac{2}{3} = \frac{10}{3} + \frac{8}{3} = \frac{18}{3} = 6 . The value matches the table, y=6 y = 6 .

  • For x=8 x = 8 :

Substitute into the equation:
y=23(8)+223=163+83=243=8 y = \frac{2}{3}(8) + 2\frac{2}{3} = \frac{16}{3} + \frac{8}{3} = \frac{24}{3} = 8 . The value matches the table, y=8 y = 8 .

  • For x=11 x = 11 :

Substitute into the equation:
y=23(11)+223=223+83=303=10 y = \frac{2}{3}(11) + 2\frac{2}{3} = \frac{22}{3} + \frac{8}{3} = \frac{30}{3} = 10 . The value matches the table, y=10 y = 10 .

Thus, the equation y=23x+223 y = \frac{2}{3}x + 2\frac{2}{3} satisfies all pairs from the table, confirming it is the correct representation.

Therefore, the correct answer is y=23x+223 y = \frac{2}{3}x + 2\frac{2}{3} .

Answer

y=23x+223 y=\frac{2}{3}x+2\frac{2}{3}