#  Applied Math 106: Applied Algebra 

 



## Lecture Notes, Handouts, and Assignments

To compile LaTeX versions of lecture notes, use [macros.tex](https://people.seas.harvard.edu/~salil/am106/fall18/macros.tex) and [header.tex](https://people.seas.harvard.edu/~salil/am106/fall18/header.tex).

Sort**Date****Title****Notes****Reading**Tue 9/4

Course Overview, Induction

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/IntroInduction.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/IntroInduction.tex)

Gallian Ch. 0

Thu 9/6

The Integers

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/Integers.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/Integers.tex)

Gallian Ch. 0

 

Problem Set 0 (due 9/14)

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/ps0.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/ps0.tex)

 

Tue 9/11

Modular Arithmetic, Relations, Algorithms

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/ModRelationsAlgorithms.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/ModRelationsAlgorithms.tex)

 

Thu 9/13

Measuring Complexity, The Euclidean Algorithm

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/Euclidean.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/Euclidean.tex)

 

 

Problem Set 1 (due 9/21)

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/ps1.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/ps1.tex)

 

Tue 9/18

Extended Euclid, Primality &amp; Factoring, Intro to Groups

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/Groups.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/Groups.tex)

Gallian Ch. 2

Thu 9/20

More Groups and Basic Properties

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/MoreGroups.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/MoreGroups.tex)

Gallian Ch. 1,2

 

Problem Set 2 (due 9/28)

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/ps2.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/ps2.tex)

 

Tue 9/25

Subgroups, Cyclic Groups

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/SubgroupsCyclic.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/SubgroupsCyclic.tex)

Gallian Ch. 3,4

Thu 9/27

Cyclic Groups &amp; Cryptography

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/CyclicCrypto.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/CyclicCrypto.tex)

Gallian Ch. 4

 

Practice Quiz I

 

 

Tue 10/2

Permutation Groups

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/PermutationGroups.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/PermutationGroups.tex)

Gallian Ch. 5

Thu 10/4

Quiz I

 

 

 

Problem Set 3 (due 10/12)

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/ps3.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/ps3.tex)

 

Tue 10/9

Isomorphisms and Cosets

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/IsomorphismsCosets.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/IsomorphismsCosets.tex)

Gallian Ch. 6-7

Thu 10/11

Cosets

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/Cosets.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/Cosets.tex)

Gallian Ch. 7

 

Problem Set 4 (due 10/19)

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/ps4.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/ps4.tex)

 

Tue 10/16

Direct Products

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/DirectProducts.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/DirectProducts.tex)

Gallian Ch. 8, 11

Thu 10/18

Normal Subgroups &amp; Factor Groups

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/NormalandFactor.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/FactorandHomomorphisms.tex)

Gallian Ch. 9

 

Problem Set 5 (due 10/26)

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/ps5.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/ps5.tex)

 

Tue 10/23

Homomorphisms, Isometries

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/HomomorphismsandIsometries.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/HomomorphismsandIsometries.tex)

Gallian Chs. 10, 27

Thu 10/25

Group Theory &amp; Crystallography

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/Crystallography.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/Crystallography.tex),  
[handout](https://people.seas.harvard.edu/~salil/am106/fall18/CrystallographyHandout.pdf)

Gallian Ch. 28

 

Problem Set 6 (due 11/2)

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/ps6plus.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/ps6.tex)

 

Tue 10/30

Rings

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/Rings.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/Rings.tex)

Gallian Chs. 12, 13

Thu 11/1

Properties of Rings

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/RingProperties.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/RingProperties.tex)

 

 

Problem Set 7 (due 11/10)

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/ps7.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/ps7.tex)

 

Tue 11/6

EthiCS Module led by [Kate Vredenburgh](https://philosophy.fas.harvard.edu/people/kate-vredenburgh):  
Basic vs. Applied Research

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/EthiCS.pdf)

[Effective Altruism](https://www.effectivealtruism.org/articles/introduction-to-effective-altruism/), [Strangers Drowning](https://people.seas.harvard.edu/~salil/am106/fall18/Excerpt%20from%20Strangers%20Drowning.pdf),  
[Mathematician's Apology](https://people.seas.harvard.edu/~salil/am106/fall18/A%20Mathematician&apos;s%20Apology%20-%20selections.pdf)

Thu 11/8

Ideals and Factor Rings

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/Ideals.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/Ideals.tex)

Gallian Ch. 14

 

Practice Quiz II

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/quiz2-practice.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/quiz2-practice.tex)

 

Tue 11/13

Ring Homomorphisms

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/Homomorphisms.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/Homomorphisms.tex)

Gallian Ch. 15

Thu 11/15

Quiz II

 

 

 

Problem Set 8 (due 11/30)

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/ps8.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/ps8.tex)

 

Tue 11/20

Polynomial Rings

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/PolyRings.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/PolyRings.tex)

Gallian Ch. 16

Thu 11/22

No Class - Thanksgiving

 

 

Tue 11/27

Factorization &amp; Ideals in Polynomial Rings, Field Extensions

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/PolyFactorizationAndIdeals.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/PolyFactorizationAndIdeals.tex)

Gallian Chs. 16-17

Thu 11/29

Vector Spaces

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/VectorSpaces.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/VectorSpaces.tex)

Gallian Ch. 19

 

Problem Set 9 (due **Monday** 12/10)

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/ps9.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/ps9.tex)

 

Tue 12/4

Error-Correcting Codes

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/Codes.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/Codes.tex)

 

Thu 12/6

Conclusions

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/Conclusions.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/Conclusions.tex)

 

 

Final Exam Practice

[pdf](https://people.seas.harvard.edu/~salil/am106/fall18/final-practice.pdf), [tex](https://people.seas.harvard.edu/~salil/am106/fall18/final-practice.tex)

 

Thu 12/13

Review Session I (7-9pm, MD 223)

 

 

Sun 12/16

Review Session II (7-9pm, MD 223)

 

 

Wed 12/19

Final Exam (9am-12pm, Harvard Hall 102)