Leon Takhtajan


Department of Mathematics
Stony Brook University

office: Math Tower 5-111
phone: (631) 632-8287
e-mail: leon.takhtajan@stonybrook.edu

MAT 534: Algebra I
Fall 2026
Schedule & Homework

Schedule


Dates Sections covered and assigned reading
Homework
Aug 24 & Aug 26 Definition of a group. Examples: symmetric group, cyclic group, dihedral group, other groups of symmetry. Homomorphisms and isomorphisms. Subgroups. Order of an element and cyclic subgroups. Cosets and Lagrange's theorem. Order of an element divides the order of the group. Normal subgroups and quotient groups.
Chapters 1-2 and §§3.1-3.2 in Chapter 3.
Problem set 1 and following problems in Dummit & Foote (page:number format): 21:1, 22:25, 28:4*, 40:17, 60:9, 86:14. due: Sep 2.
Aug 31 & Sep 2 Quotient groups. Isomorphism theorem. Direct and semidirect products. Simple groups. Holder's theorem (no proof). Group actions on sets; orbits and stabilizers.
Ch.3, §§3.3-3.5, Ch.4, § 4.1 and Ch. 5, §5.1 and §§5.4-5.5 (up to p. 180).
Problem set 2 due: Sep 9.
Sep 7 & Sep 9 Action by conjugation and class equation. Solvability of p-groups. Sylow theorems.
Ch.4, §§4.3-4.5.
Problem set 3 due: Sep 16.
Sep 14 & Sep 16 Sylow theorems and their applications. Classification of groups of small orders. Introduction to symmetric and alternating groups.
Ch.4, §§4.5-4.6 and Ch.5, §§5.3-5.5.
Problem set 4 due: Sep 23
Sep 21 & Sep 23 Symmetric and alternating groups continued. Classification of finitely generated abelian groups, main theorem and unqieness. Torsion subgroup and rank. Free groups.
Ch.5, §5.2, Ch.6, §6.1 pp. 196-198, §6.3. §§5.3-5.5, and S. Lang Algebra, Ch. 1, §8.
Problem set 5 due: Sep 30