One Step Subgroup Test | Abstract Algebra Exercises

We prove the one-step subgroup test for showing a nonempty subset of a group is a subgroup. We also do a one step subgroup test example, showing the powers of 2 make a subgroup of the multiplicative reals using the one step test. The test is as follows: If H is a nonempty subset of a group G, and if a,b in H implies ab^-1 is in H, then H is a subgroup of G. #abstractalgebra

All About Subgroups:    • All About Subgroups | Abstract Algebra  
Two Step Subgroup Test:    • Two Step Subgroup Test | Abstract Alg...  
Finite Subgroup Test:    • Finite Subgroup Test | Abstract Algeb...  
One Step, Two Step, and Finite Subgroup Tests:    • Two Step, One Step, and Finite Subgro...  

Abstract Algebra Course:    • Abstract Algebra  
Abstract Algebra Exercises:    • Abstract Algebra Exercises  

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