Updated: September 6, 2006


MTH 307 - Fall 2006

Introduction to Mathematical Rigor


Sec. 1 Meets MWF:  11:00-11:50 – Wales 223

Instructor:  Dr. Nancy Eaton

E-mail me:
Phone:  874-4439
Office:  Rm. 222, Tyler Hall
Office hours:  MTW 9-10 and

MTW 8-9 by apt.

Visit my web page:

Students who require accommodations and who have documentation from
Disability Services (874-2098) should make arrangements with me as soon as possible. 

Course Description


Grade for course

Working with Others

Dates to Remember

What is Math

Other Web Resources

Rubric used for grading

Class Notes


Using MS Word equation editor

Keys to Exams

Homework  Assignments 

Solutions to selected exercises

Practice for Exams 

Portfolio assignment



Course Description:

Provides a bridge between lower level and upper level mathematics courses, where proofs of mathematical statements are discussed.  The emphasis is on basic structures, logic, the structure of mathematical statements, and proof techniques.  Theorems and problems from many areas of mathematics serve as motivation and come from a wide range of topics including set theory, number theory, abstract algebra, geometry, discrete math, and continuous math.

1.  Become familiar with and correctly use the basic structures of mathematics.

a.       Recognize and interpret the meaning of the terms and symbols used in set notation for unions and intersections of any number of sets, for the complement of a set, and for the Cartesian product of sets and n-tuples.

b.      Recognize and form partitions of sets and name the corresponding equivalence classes.

c.       Distinguish the different number systems, including natural numbers, integers, rational numbers, real numbers, and complex numbers and explain their respective constructs.

d.      Interpret addition, subtraction, multiplication, and division as binary operations on numbers and explain how subtraction and division can be defined in terms of addition and multiplication, respectively.

e.       Explain the meaning of the equal sign in terms of equivalent expressions that can be substituted, one for the other in other equations.

f.        Recall the field and ordered field axioms and apply them in the justification of some basic identities and inequalities for real numbers.

g.       Express the summation and product of multiple terms, using sigma and pi notation and manipulate expressions that contain these symbols.

h.       Relate the basic definitions of functions, injections, surjections and bijections.

i.         Identify and employ the basic operations on functions, including addition, multiplication, and composition

j.        Identify and formulate the inverse of a function and interpret the meaning in terms of the inverse under composition of functions.

k.      Distinguish between the various uses of negative one in the exponent.

l.         Establish cardinality of sets, both finite and infinite.

m.     Recall definitions and properly apply counting terms and principles.

2.  Learn the many aspects of logic and correct reasoning to both understand and prove theorems.

a.       Produce proofs of set equalities and inclusions using basic set theory principles.

b.      Translate between mathematical statements, written in ordinary English and using quantifiers, both universal and existential.

c.       Distinguish the types of mathematical statements, such as implications and if and only if statements.

d.      Use truth tables to establish equivalence between mathematical statements.

e.       Identify the hypothesis and the conclusion of an implication.

f.        Form the converse, contrapositive, and negation of statements containing implications and quantifiers.

g.       Form the negation of any mathematical statement and form counterexamples to false statements.

h.       Employ any of the proof methods: direct proof, induction, contradiction, and proving the contrapositive, to formulate a proof of an elementary result.

i.         Apply basic proof techniques, the Pigeonhole Principle, and combinatorial reasoning to prove some elementary counting theorems that are used in probability and combinatorics.

j.        Apply basic proof techniques to statements about the injectivity and surjectivity of functions.

3. Additionally, topics from the following list will be covered in the course.

a.       Set Theory (e.g. DeMorgan’s Laws, Cardinality)

b.      Geometry:  Axioms and theorems, Pythagorean Theorem

c.       Algebra (e.g. Algebraic identities, Quadratic Formula, Geometric Sum Identity, Binomial Theorem)

d.      Real Functions (e.g. Ceiling, Floor, and Greatest Integer Functions, bounded functions, Monotone functions)

e.       Real Numbers (e.g. Ordered field axioms and theorems)

f.        Discrete Mathematics (e.g. Counting formulas and principles, graph theory)

g.       Number Theory (e.g. Divisibility, q-ary representations of numbers, Division Algorithm)  


Text:  A Discrete Transition to Advanced Mathematics by Bettina Richmond and Thomas Richmond, Thomson Brooks/Cole Pubs.

Calculation of Grade:

Homework - 25%
Portfolio - 25%
Three 1-hour exams - 30%
Final - 20%



Homework Assignments: (25% of your grade)

I assign many problems from the book and other sources.  You are expected to do them all.

HkPts System:  From those suggested, I will assign assign many more than 40 to hand in.  Follow the guide.  These will be graded and comments will be given.    Each is worth up to 4 HkPts. (See the grading rubrik.) Your goal is to get as close to 160 HkPts as possible.

Earning extra HkPts: 

*       You can earn extra Hkpts by hanking in more than a total of 40 assigned problems.

*       Also, during the semester, you will be asked to present solutions to the assigned problems on the board.  These will be chosen from those that you do not hand in.  You will always be given a chance to prepare your presentation.  This will serve to improve your verbal communication skills. You will be graded on your presentation and earn up to 2 HkPts for each solution.

*       Class work for extra credit is sometimes given – you must be in class to receive these points.

Here are some tips in doing homework.

*       Try each problem on your own.

*       Check your answer with the back of the book or someone in class.

*       Go over each problem with someone in the class.

*       Ask me about the ones that you still do not completely understand.

*       Take notes whenever we go over a problem in class.

*       Carefully write a final version of each problem, as best you can, and keep them together in a binder.

Portfolio: (25% of your grade)

From the suggested homework problems, I will select 10 for you to rewrite and hand in as a portfolio of work, representing what you learned in this course.  This is intended to be a collection of your best work.  This will be due on Monday December 11th. You will have two weeks advance notice as to which problems will be included in the portfolio. The problems will be listed on this web page on November 27th. The intention here is that you will make sure you understand how to solve each homework problem as we go along, in case it will be selected to be in the portfolio.

Write out the entire statement of the exercises.  Write the solution as formally as you can.  Use complete sentences.  Write it as if it would be published.  In fact, I will publish selected solutions on the web!  This MUST BE TYPED.  It is okay to type the sentences and leave spaces for writing equations by hand.  If you have access to an equation editor, that would be best.  See: link.

Portfolio problems

Sec 1.2 – 7

Sec 1.4 – 6

Sec 2.1 – 5c, 10

Sec 2.2 – 2c

Sec 2.3 – 2 Use P.P to explain if applicable.

Sec 3.1 – 7e

Sec 6.1 – 12, 19

Sec 6.2 - 12

Guide to working with others:

There are benefits to discussing the problems with your classmates.  If you become stuck on a problem, fresh ideas from someone else might provide you with some new angles to try.  In the academic community as well as in business and industry, people often work in teams.  So, it is good to get some practice working with others.  Working with someone from class will help you to improve your math communication skills as well.

I encourage you to work together under the following circumstances.

*  Begin the problem on your own and do as much as you can.

*  Ask someone from the class to explain the basic outline of a solution.

*  If working with someone else, sometimes they will also ask you for your understanding of the basic outline.

*  Take what you learned and write out the solution on your own, using your own words. 

*  Never copy word for word from anyone else’s paper.  In fact it is better not to look at anyone else’s completed written solution or to show yours to anyone else.

*  If you still do not completely understand the solution, you can ask your professor to look at what you wrote and try to clear up any parts of the solution that are not completely clear and accurate. 

The following is an excerpt from the University Manual.

8.27.11 A student's name on any written exercise (theme, report, notebook, paper, examination) shall be regarded as assurance that the work is the result of the student's own thought and study, stated in the student's own words and produced without assistance, except as quotation marks, references and footnotes acknowledge the use of other sources of assistance. Occasionally, students may be authorized to work jointly, but such effort must be indicated as joint on the work submitted.  Submitting the same paper for more than one course is considered a breach of academic integrity unless prior approval is given by the instructors.


Exams: (Exams 30%, Final 20%)

There will be three 45-minute exams. The dates for these are Oct. 11, Nov 6, and Dec 4. The final exam is will be given during the scheduled time on Friday Dec. 15 from 11:30 - 2:30 PM.  The exams will be taken from material that we covered in class or in homework assignments, so take careful notes and study them for the exams.

Dates to remember:

Exam 1:  Oct 11; Exam 2:  Nov 6; Exam 3:  Dec 4
Portfolio:  Nov 27 (problems announced),
Dec 11 (portfolio due)
Final Exam:  Dec 15

Homework assignments:  

Homework assignments will be given in class and recorded here for your reference.  You must do the following for full credit on the assignments that you hand in.




AA)Write out the entire question.

BB) Write neatly or type your assignment. Do not use torn paper.

CC)The format should be single column, double-spaced.

DD) Use only one side of the paper.

EE)Clearly mark the assignment number and due date on the top of the front page.

FF)Arrange the exercises in order by problem number. Attach pages together.

GG) One point will be deducted from the assignment for each class day that it is late.


Explain carefully, using proper mathematical logic.

Use complete sentences.



Do all

Hand In

Due Date

Assignment #


1, 2, 3, 5(a-d), 8

 2, 5(a), 8

Sept 13



1, 2, 4-8, 12, 13, 15, 16

4, 8, 12,

Sept 13



3, 6, 7, 9, 10, 12

6, 10

Sept 20




8, 9

Sept 22



1(a, c, d), 2(a, b), 3, 6

4(b), 4(c)

Sept 25



1-3, 6, 9-11

6(a), 9(b)

Sept 25



2, 4-8, 10, 13, 14, 17, 24


Oct 2



14, 24

Oct 2




Exam 1

Oct 13



2(a, b, d), 3, 10, 12, 13, 14(a, b), 15

4, 10, 12

Oct 20



1-4, 7

2, 4

Oct 20



2, 3, 4, 9, 15, 16, 20, 24

2, 4, 16

Oct 25



1, 3, 5, 6, 7

6(b), 6(c)

Oct 25



2 – 8

4, 6

Nov 1



1 – 11

2, 4, 6, 8

Nov 1




Exam 2

Nov 6



5, 6, 15





1, 2, 3, 4





3, 4, 6, 7, 9, 11, 19

4, 6

Nov 17



2, 3, 5, 8 – 14

2, 8, 6(not part e), 10

Nov 20



Worksheet A

Worksheet A - All

Nov 27



2, 3, 7, 9


Nov 27



2, 3, 4, 5, 6, 11, 12

2, 4, 6, 12

Dec 1



Worksheet B

WorksheetB - All

Dec 1




Exam 3

Dec 6





Dec 11



1, 2, 3, 14

2, 14

 Dec 11



2, 3, 5, 6

2, 6

 Dec 11





Dec 15


Class Notes

Packet1  Packet2 Packet3  Packet4  Packet5

Packet6 (Sec 2.1)  Packet7 (Sec 2.2)  Packet8 (Sec 2.3)

Binomial Theorem

Packet9 (Sec 6.1)  Packet10 (Sec 6.2) Packet11 (Sec 6.3)


Solutions to selected homework problems and examples:

Chapter 6

Keys to exams:

Key to Exam 1

Key to Exam 2

Key to Exam 3

Practice for exams:

Exam 1  Solution Key to Exam 1 

Exam 2  Solution Key to Exam 2   (For exam 2 – ignore #4)  (For exam 3 – see #4)

Exam 3  Solution Key to Exam 3   (For exam 2 – see #4, 5, 7)  (For exam 3 – ignore #4, 5, 7)


Some Web Sites:

Proofs in Mathematics

Fermat's Last Theorem
Puzzles -
Recreational Math


What is Math?

Throughout the semester, you may submit answers to these questions via e-mail.  I will post your answers on our web page and indicate the author.  If you quote someone else, please indicate.

1. What is mathematics?

Math is a language, which we use in society to communicate quantities and the intermediate operations which are used to obtain these quantities. Like with English, Spanish, German, or Russian, there are many things we can say about the different things we encounter; but when it comes to expressing numbers, humans have found that there is a need for an additional language, math. - Jason Stockford

Mathematics is the Science of numbers and of space configurations. -Webster Dictionary

To the question what is math: "My hypothisis-1. Mathematics is the language of nature. 2. Everything around us can be represented and understood through numbers.3. If you graph these numbers, patterns emerge. Therefore: There are patterns everywhere in nature." Maximillian Cohen from the movie Pi


Mathematics is an arithmetic interpretation and study of the physical world.  Math is a natural language that defines the actions of natural occurrences and it gives us the ability to interpret those actions.  –Amy Brown

Mathematics is the study of quantity, structure, space and change. It developed, through the use of abstraction and logical reasoning, from counting, calculation, measurement, and the study of the shapes and motions of physical objects. (Wikipedia encyclopedia)


Math is the representation of numbers in any universe and dimension. It is the understanding of numerical expressions and their relationship to everything in our lives, from time, to the numbers of chairs at a wedding, to complex ideas such as their discrete and infinite properties. It is the understanding of patterns in nature and on paper. –A.Koster


Mathematics is "the study of the measurement, properties, and relationships of quantities and sets, using numbers and symbols"

Math is a language that describes the laws of nature. -Professor Gerry Ladas.

Mathematics is a science (or group of related sciences) dealing with the logic of quantity and shape and arrangement and it is a study of well-defined concepts. and Daniel Henry Gottlieb


2. How does math benefit society?

"In most sciences, one generation tears down what another has built and what one has established another undoes.  In Mathematics alone each generation builds a new story to an old structure." ~Hermann Hankel

Math benefits society in many ways, which people who are poorly educated in math do not realize. For instance, we can speak of one of the most well known areas of math, Calculus. Calculus is something that many students fear, but what few realize is that Calculus does not complicate that which is simple, but rather just the opposite. Calculus enables people from a broad array of professions to tackle difficult problems with much more ease then would be possible if everything needed to be done using brute force. For example, engineers often are required to find areas, volumes, or centers of mass in irregular shaped objects, and with the relatively simple concept of the definite integral these engineers who must find precise answers may do so without the pure drudgery of computing a huge number of Riemann sums. - Jason Stockford

It is the basis of interpretation of science.  Mathematics is repetitive, unique, and it is used in development of all technological advances since the beginning of history.  It is used to define and explain the universe, solar system, and the world.  Math has been used as society has evolved monetarily, technically, and scientifically. – Amy Brown

Mathematics benefits society because it is the job of predicting and calculating things that are important or valuable for us to know, the job of being sure those predictions and calculations are right, and the job of discovering new truths that may one day be essential to ensuring a better life for us all.  (


Math is used all over the world all of the time. Although not everyone understands the more complex equations and problems, everyone uses math every day. From calculating a tip at a restaurant, to determining how much you are saving when a shirt goes on sale 25%. We are able to understand why as we drive farther in our cars, the odometer continues to grow. In some cultures that depend on hunting, they are able to count how much food they have left and hunt and gather depending on how much they need. We all understand that you can never tangibly see a negative amount of something. –A.Koster


Practical mathematics, in nearly every society, is used for such purposes as accounting, measuring land, or predicting astronomical events. Mathematical discovery or research often involves discovering and cataloging patterns, without regard for application. The remarkable fact that the "purest" mathematics often turns out to have practical applications is what Eugene Wigner has called "the unreasonable effectiveness of mathematics." Today, the natural sciences, engineering, economics, and medicine depend heavily on new mathematical discoveries.( encyclopedia).


Mathematics is involved in every aspect of life, whether it be shopping at the mall, or discovering a cure for cancer.  Math provides us with the possibility of always acquiring new knowledge.~H. Hazard

3. Why do universities usually have a department devoted to the study of mathematics?

Math is something that is still developing, and everyday mathematicians are finding new solutions to old problems and applying old problems to new applications. Colleges and Universities are at the core of almost all research done in the world today, so it only makes sense that colleges and universities would have departments devoted solely to the study of math. – J. Stockford

Math is essential to all the related physical sciences.  A separate department is devoted for math because of the need for future research and development.  It is the basis of explaining the world.“To think the thinkable-that is the mathematician’s aim.”-C.J. Keyser


Universities realize that mathematical expertise is more important than ever, particularly in computers and high-technology areas.  Having a mathematics department at a university prepares students for employment in the mathematical sciences or for future study. Mathematics degree concentration opportunities combine math study with philosophy, economics, computer science, and math education. Universities know that all of these areas are an essential part of life and that without math they would not be possible. –H.Lally


Math is continuously growing. New ideas are always being proven, and old ones are constantly being replaced in order to make them more understandable. Many people have been pulled into the idea of possibly proving something new or improving an old idea. It is like a workout for the brain, and our society sure it obsessed with working out any portion of our body. A university is the easiest place to allow intelligent minds to gather and think up ideas and work on issues together. It combines the efforts, so that more things can be done quicker. One person might be so close to proving something but are just missing one small variable, and after showing it to a co-worker, who notices the small mistake, this large issue has all of a sudden been solved. It is also one of the easiest ways to get students involved and interested in the study of math. –A.Koster


Universities have departments devoted to mathematics because mathematics is an on going learning process.  While most of the information known about mathematics is grounded, there will always be someone that is able to take a particular concept further.  Math departments at the university level are here to broaden the mind frame and to establish new information in its pupils.  Not only this, but it is a known fact that much of our lives revolve around mathematics, and college is the stepping stone to life, so mathematics must be an integral part in our getting ready to take on life~Heather Hazard


Colleges know that mathematics is important and they have their own departments for it because it is used for so many different jobs.  You have to take different math classes for every major that you are in but it is very important you take those classes.  Since all students can't take engineering classes that have to offer many different classes. – Jessica Weil



4. How will learning mathematics help you in your career other than that it is required for your degree?

Being able to figure out math problems requires a certain amount of logic and, companies, which are hiring new graduates may consider people with degrees in math to be more valuable then people with other degrees for that reason. People who are good in math tend to be good decision makers and they tend to analyze problems that arise, in a logical manner. These are both positive things which competitive employers look for when choosing applicants. – J. Stockford

Math is logical, methodical reasoning, problem solving and a thought process.  It is important in understanding the structure of nature.  Math provides an overall well rounded intelligence and gives a basic understanding of all other disciplines.  Without math we would not have a society.  Currency, economics, biology, and medicine are just a few fields, who’s  foundation is based on math. “A mathematician, like a painter or poet, is a maker of patterns.  If his patterns are more permanent than theirs, it is because they are made of ideas.” -G.H. Hardy


Mathematics is a field that can be used in many different careers.  Pretty much every occupation you want to get into requires some type of math.  In your job you may have to calculate interest rates or work with money.  Mathematics is used often in fields like accounting, engineering, science, and economics.  Knowing different ways to work with numbers will make ordinary calculations a lot easier and less time consuming.  Therefore allowing you to have more time to do work on more difficult things and not have to worry about simple math.  H. Lally


Math allows for me to be able to problem solve quicker. By knowing how to do something quite complex well, I will be able to do all of those easier concepts just that much faster. You must be able to problem-solve and work through something until you reach a conclusion. Employers are looking for these qualities when they go to hire someone. There is not one job that does not involve some understanding of math. Engineers use it to understand the forces involved in what they are creating; Economists need to be able to understand numbers and their meanings in statistics, etc; Hairdressers must understand exactly what a client means when they say they only want one inch off. Personally I am a math major because as a career I would like to work in the Power and Energy field specifically with wind power. I must be able to understand the financing of the projects, the statistical data that is found through the wind in the area, the dimensions of projects, etc.


Seeing how i am going to be a math teacher, mathematics has to be at the basis of my knowledge.  Teaching to me, is being able to teach another person how to be prepared to succeed in life.  In order for a person to succeed, they are going to need at least some minimal knowledge of mathematics.  Therefore it is important that i know all that i can to be able to pass it on to another person.  –H.Hazard


Since I am going to be a math teacher it is important I am skilled in all areas of mathematics.  Even though I want to teach middle school algebra, I think it is important that I know some of the higher math also.  If the students ever need help in later years they will know they can come to me. –Jessica Weil