Articles containing proofs | Theorems in group theory

Subgroups of cyclic groups

In abstract algebra, every subgroup of a cyclic group is cyclic. Moreover, for a finite cyclic group of order n, every subgroup's order is a divisor of n, and there is exactly one subgroup for each divisor. This result has been called the fundamental theorem of cyclic groups. (Wikipedia).

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Abstract Algebra | Subgroups of Cyclic Groups

We prove that all subgroups of cyclic groups are themselves cyclic. http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/

From playlist Abstract Algebra

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Abstract Algebra | Cyclic Subgroups

We define the notion of a cyclic subgroup and give a few examples. http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/

From playlist Abstract Algebra

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Cyclic Groups, Generators, and Cyclic Subgroups | Abstract Algebra

We introduce cyclic groups, generators of cyclic groups, and cyclic subgroups. We discuss an isomorphism from finite cyclic groups to the integers mod n, as well as an isomorphism from infinite cyclic groups to the integers. We establish a cyclic group of order n is isomorphic to Zn, and a

From playlist Abstract Algebra

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Visual Group Theory, Lecture 2.1: Cyclic and abelian groups

Visual Group Theory, Lecture 2.1: Cyclic and abelian groups In this lecture, we introduce two important families of groups: (1) "cyclic groups", which are those that can be generated by a single element, and (2) "abelian groups", which are those for which multiplication commutes. Addition

From playlist Visual Group Theory

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Cyclic groups and finite groups

Jacob goes into detail on some particularly important finite groups, and explains how groups and subgroups can be generated by their elements, along with some important consequences.

From playlist Basics: Group Theory

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Definition of a Cyclic Group with Examples

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Definition of a Cyclic Group with Examples

From playlist Abstract Algebra

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Abstract Algebra - 3.3 Examples of Subgroups: The Cyclic Subgroup and the Center

Now that we know how to determine if a subset is a subgroup, let's take a look at two subgroups we should become familiar with. The first is the cyclic subgroup. We will devote our next chapter to cyclic groups, but you'll find we have already discussed generators and cyclic groups when di

From playlist Abstract Algebra - Entire Course

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Cyclic Groups (Abstract Algebra)

Cyclic groups are the building blocks of abelian groups. There are finite and infinite cyclic groups. In this video we will define cyclic groups, give a list of all cyclic groups, talk about the name “cyclic,” and see why they are so essential in abstract algebra. Be sure to subscribe s

From playlist Abstract Algebra

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Group theory 15:Groups of order 12

This lecture is part of an online mathematics course on group theory. It uses the Sylow theorems to classify the groups of order 12, and finds their subgroups.

From playlist Group theory

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Cyclic Groups -- Abstract Algebra 7

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From playlist Abstract Algebra

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Lie Groups and Lie Algebras: Lesson 44 Group Theory Review #3 (corrected!)

Lie Groups and Lie Algebras: Lesson 44 Group Theory Review #3 This is a corrected version of a previous upload. In the earlier version I ridiculously stated that cyclic subgroups were normal. I don't know what came over me, that is certainly NOT true. What is true is that if a group is a

From playlist Lie Groups and Lie Algebras

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Cyclic Groups in Cryptography

Some detail about cyclic groups and their application to cryptography, especially Diffie Hellman Key Exchange.

From playlist PubKey

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Abstract Algebra | Third isomorphism application.

We use the third isomorphism to prove a result that would have definitely been easier to prove some other way.... http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/

From playlist Abstract Algebra

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Abstract Algebra - 4.3 Classification of Subgroups of Cyclic Groups

In this video we look at the fundamental theorem of cyclic groups and the Euler Phi function. I ended the video with some great practice of the theorems learned in this chapter. Video Chapters: Intro 0:00 Fundamental Theorem of Cyclic Groups 0:08 Corollary for Zn 5:35 Euler Phi Function 1

From playlist Abstract Algebra - Entire Course

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Abstract Algebra April 20

Suggest a problem: https://forms.gle/ea7Pw7HcKePGB4my5 Please Subscribe: https://www.youtube.com/michaelpennmath?sub_confirmation=1 Merch: https://teespring.com/stores/michael-penn-math Personal Website: http://www.michael-penn.net Randolph College Math: http://www.randolphcollege.edu/ma

From playlist Super Lo-fi in class videos

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Every Subgroup of a Cyclic Group is Cyclic | Abstract Algebra

We prove that all subgroups of cyclic groups are themselves cyclic. We will need Euclid's division algorithm/Euclid's division lemma for this proof. We take an arbitrary subgroup H from our Cyclic group G, then we take an arbitrary element a^t from H. Certainly, all powers of a^t are in H,

From playlist Abstract Algebra

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The Klein Four-Group

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys The Klein Four-Group is the smallest noncyclic abelian group. Every proper subgroup is cyclic. We look at the the multiplication in the Klein Four-Group and find all of it's subgroups.

From playlist Abstract Algebra

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Abstract Algebra 1.6 : Subgroups, Lagrange's Theorem, and the Center

In this video, I introduce Lagranges theorem, using it and other facts to prove many things about groups and their subgroups. I then introduce the center of a group and use it to prove that groups of order prime squared (|G| = p^2) are abelian. Email : fematikaqna@gmail.com Subreddit : ht

From playlist Abstract Algebra

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Group theory 16: Automorphisms of cyclic groups

This lecture is part of an online mathematics course on group theory. It is mostly about the structure of the group of automorphisms of a cyclic group. As an application we classify the groups of order pq for primes p, q.

From playlist Group theory

Related pages

Nielsen–Schreier theorem | Free group | Finitely generated group | Locally cyclic group | Subgroup | Abstract algebra | Quotient group | Rational number | Duality (order theory) | Lattice of subgroups | Cyclic group | Distributive lattice | Finite group