A function graph with integer inputs

Compare this dot plot with the bar graphs in class. Here, each pair represents an input x and an output f(x); In a bar chart, the horizontal axis can also represent categories.

Em telas pequenas, deslize o gráfico na horizontal para ler os detalhes.

Change the rule and look at the table. We do not connect the dots when the domain is ℤ.
What happens when a = 0?

The function is constant: f(x) = b. The points have the same vertical coordinate, but remain separate when the domain is ℤ.

Graphic notion is important for children, as it can facilitate the understanding of the information summarized in this visual representation. Having seen all the concepts of the Cartesian plane, the next step is to talk about graphs, in this case, for integers. However, for this numerical group it is necessary to keep classification concepts in mind. This is a very old habit of human beings, classifying everything around them.

Graphic

But what is a graphic?

A graph is a visual resource to represent a phenomenon that can be measured (measured), quantified (in terms of quantity).

Importance of graphics

Sometimes, in a graph, information is easier to understand than in purely numerical terms. Therefore, many companies ask their employees to represent information graphically instead of numerically.

This resource, if used well, can speed up the understanding of information. Many managers generally have little time in meetings.

Employees, most of the time, only have a few minutes to convince these managers. Therefore, the graphic resource is the way to shorten understanding.

Professions that use graphics well

In the past, most companies were not very concerned about the information they collected and did not take advantage of its potential. Today, those who do not work well with this information are left behind.

The success of companies in the modern world is one that evaluates the information collected well. Therefore, the fastest growing segments in the world are information technology and statistics.

Bar chart

The bar chart is formed by rectangles, where the height of the rectangle represents the quantity or count of a certain category. The categories are represented on the $x$ axis of the Cartesian plane and the count on the $y.$ axis

Example: On a school trip for students from a primary elementary school, there are students of different ages. The monitor wants to know how many students are on the trip. The first idea is to make a bar chart.

Age $= \\{6, 6,6,6,7,6,7,6,9, 10, 9,9,9,10,7,5,6,8,8,8,8,10\\}$

The numerical view is given by the sum of children by age.

Age (years) Counting (Children)
5 1
6 7
7 3
8 4
9 4
10 3

The graphical view is given by the bar graph.

Children ages five to ten with counts one, seven, three, four, four and three.
Values ​​same as in the table: compare each bar with your count.
Ampliar figura para ler os detalhes
Children ages five to ten with counts one, seven, three, four, four and three.

Bar chart by groups

Example: A supermarket wants to check the number of payment methods

  • debit card,
  • credit card and
  • money

To do this, it was divided into periods of the day

  • morning,
  • late and
  • night
Payment Type Period Count
Debit card Morning 28
credit card Morning 11
Money Morning 18
Debit card Afternoon 70
credit card Afternoon 15
Money Afternoon 33
Debit card Night 130
credit card Night 83
Money Night 101

With these amounts of payment methods counted per period of the day, we will build the bar chart.

Debit, credit and cash payments in the morning, afternoon and evening.
The values ​​are indicated over the bars.
Ampliar figura para ler os detalhes
Debit, credit and cash payments in the morning, afternoon and evening.

These are some of the possible graphs that we can construct from integers. In other posts we will build graphs from other types of numerical sets.