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Roster and builder set forms

A group of items can be represented in several ways. Set is one of the ways in which a group of similar items can be represented. This article has discussed the different forms of a set with examples.

A set is represented as the collection of particles. Sets are denoted and represented with a capital letter. Humans, letters of alphabet, numbers, forms, variables, and so on are all examples of items that make up a set in set theory. A set in roster form is one of the easiest ways to represent and comprehend the concept of a set. 

A collection of natural even digits smaller than ten is defined, but a group of bright pupils in a class is not. As a result, a set A = 2, 4, 6, 8 can be used to denote a group of the even natural numbers less than 10.

Cardiac Number of Set

The total number of items in a set is denoted by the cardinality or the cardinal number of orders. A collection of distinct elements is known as a set. One of the essential requirements for defining a set is that its elements must be related to one another and share a common feature.

Representation of a Set

For the denotation of sets, various set notations are employed. The order in which the objects are listed differs. The following are the 3 set notations that are used to represent sets.

  • Set builder form

  • Roster form

  • Semantic form

Semantic Form

A = 2, 4, 6, 8 

The semantic symbol is a declaration that shows which items make up a set. Set A (see above), for instance, is a list of the 1st five even digits.

Roster Form

The roster notation, in which the elements of the sets are contained in the brackets differently by commas, is the most frequent way to represent sets.

Let’s see the examples below for a summary of the roster form notation.

Set A = {1, 2, 3, 4, 5}; 

Sets in infinite roster notation: Set B ={ 5, 10, 15, 20, 30, 40, 50, (The multiples of 5)}.

Set Builder Form

There is a rule or a statement in the set-builder notation that describes the common trait of all the elements of the set. The set builder form is represented as a vertical bar with text explaining the character of the set’s elements. A = {k | k, for example, is an even number, k< 20}. According to the statement, all of the components of set A are even numbers less than or equal to 20. In some cases, a “:” is used instead of a “|.”

Sets of Various Types

There are several different sorts of sets. Singleton, finite, infinite, and empty sets are some of them.

Singleton Sets

A singleton set, also known as a unit set, is a set with only one element. Set A ={ k | k is an integer between 3 and 5}, resulting in A = {4}.

Finite Sets

As the name implies, a finite set is a set with a finite or countable number of items. 

Set B = {k | k is a prime number smaller than 20}, for example, is B = {2,3,5,7,11,13,17,19}.

Infinite Sets

An infinite set is a set containing an unlimited number of items.

Example: B ={ 5, 10, 15, 20, 30, 40, 50, (The multiples of 5)}

Empty or Null Sets

An empty set, also known as a null set, is a set that has no elements. The symbol ” is used to represent an empty set. It’s pronounced ‘phi.’ Set X = {a|a is a natural number between 4 and 5}.

Equal Sets

When two sets contain the same items, they are referred to as equal sets. A = {1,2,3} and B = {1,2,3} are two examples. Sets A and B are equal in this case. A = B can be used to represent this.

Unequal Sets

Unequal sets are those that have at least one element that is different.

A = {1,2,3} and B = {2,3,4} are two examples. Sets A and B are unequal in this case. A≠B can be used to indicate this.

Sets of Equivalents

When two sets contain the same number of elements but distinct elements, they are said to be equivalent sets. For instance, A = {1,2,3,4} and B = {a,b,c,d}. Because n(A) = n(B), sets A and B are equivalent (B)

Overlapping Sets

If at least one element from set A appears in set B, the two sets are said to overlap. A = {2,4,6} B = {4,8,10} is an example. Element 4 appears in both sets A and B in this case. As a result, A and B are two sets that overlap.

Disjoint Sets

If there are no shared elements in both sets, they are disjoint sets. For instance, A = {1,2,3,4 }and B = {5,6,7,8}. Sets A and B are disjoint in this case.

Conclusion

The components that make up a set are referred to as elements or members of the set. Curly brackets separate the elements in a set, which are separated by commas. The sign ∈ is used to indicate that an element is part of a set. There are several different sorts of sets. Singleton, finite, infinite, empty, and a few others are some of them. An empty set, also known as a null set, is a set that has no elements. The symbol ‘φ’ is used to represent an empty set. It’s pronounced ‘phi.’

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What is an element of a set?

Answer: An element of a set refers to each object in the set. These elements are enclosed in brackets, separa...Read full

What is the definition of roster form?

Answer: The roster notation, in which the elements of the set are contained in curly brackets separated by co...Read full

Name a few types of sets.

Answer: Supersets, equivalent sets, singleton sets, disjoint sets, power sets, finite sets, overlapping sets,...Read full

How do Venn Diagrams illustrate sets?

Answer: Sets are depicted by circles formed inside a rectangle representing the universal set in a Venn diagr...Read full