TOC
Courses
Blog
Twitch
Shop
Search
Toggle menu
Courses
Blog
Subreddit
Discord
Log in
Sign up
▾
Abstract algebra
▸
Binary operations and relations
•
Properties of binary operations
•
What is a relation? (for undergraduates)
•
What is an equivalence relation?
▾
Group theory
•
Intro to groups
•
Subgroups
•
Group isomorphisms
▸
Group homomorphisms
•
Kernel of a group homomorphism
•
Intro to group homomorphisms
•
Equivalence classes
•
Cosets of a subgroup
•
Cosets and Lagrange's theorem
•
Basic group theory proofs
▸
Abelian groups
•
Lesson
•
Practice
•
Alternating groups
•
Tidbits on Burnside's lemma
▸
Converting between array notation and cycle notation
•
Converting cycle notation to array notation
•
Converting array notation to cycle notation
•
Cyclic groups
•
Dihedral group
•
Direct product of finite cyclic groups
•
Direct product of groups
•
Group automorphisms
•
Is the table a commutative semigroup?
•
Kernel of a group homomorphism
•
Klein four-group
•
Multiplying permutations in array notation
•
Multiplying permutations in cycle notation
•
Order of an element in a group
•
Proof: Centralizer of group element is subgroup
•
Compositions of group morphisms
•
Normal subgroups
•
Proof: Finite subgroup test
•
Proof: First isomorphism theorem for groups
•
Proof: Fundamental homomorphism theorem
•
Proof: Group abelian iff cross cancellation property
•
Proof: If \(y\) is a left or right inverse for \(x\) in a group, then \(y\) is the inverse of \(x\)
•
Proof: Inverse of generator of cyclic group is generator
•
Proof: Inverse of group inverse
•
One-step subgroup test
•
Proof: Order of element divides order of finite group
•
Proof: Order of group element equals order of inverse
•
Proof: Second isomorphism theorem for groups
•
Proof: Special linear group is subgroup of general linear group
•
Proof: Symmetric difference on power set forms group
•
Proof: The conjugation map is an automorphism
•
Proof: Two-step subgroup test
•
Proving group homomorphisms
•
Quotient groups
•
Simple groups
•
Solvable groups
•
Sufficient conditions for a group to be abelian
•
Symmetric group
•
Symmetries of an equilateral triangle
•
Verifying equivalence relations on groups
•
What is cycle notation?
•
Group actions
•
Orbit stabilizer theorem
•
Center of a group
▸
Ring theory
•
Is it a ring?
•
Basic ring theory proofs
▸
Integral ideals
•
Intro to integral ideals
•
Proving multiples form an integral ideal
•
More ring theory proofs
•
What is a subring?
›
Abstract algebra
›
Group theory
Proof: Inverse of group inverse
\(\left(g^{-1}\right)^{-1} = g\)
70454
Proof: Group Element is the Inverse of its Inverse | Group Theory, Abstract Algebra
Wrath of Math
44096
Proof that in a Group the Inverse of g^(-1) is g, so (g^(-1))^(-1) = g
The Math Sorcerer
777
Inverse of Group Inverse
ProofWiki