4: Subgroups Last updated Save as PDF Page ID 84809 Jessica K. Sklar Pacific Lutheran University 4.1: Introduction to Subgroups Sometimes groups are too complicated to understand directly. One method that can be used to identify a group's structure is to study its subgroups. 4.2: Subgroup Proofs and Lattices Using Lemma 4.1.1 and the argument preceding it, we have the subgroup proofs and lattices in this section. 4.3: Exercises This page contains the exercises for Chapter 4.