# Mathematical Reasoning: Writing and Proof, Version 2.1

Ted Sundstrom, Grand Valley State University

Copyright Year: 2014

ISBN 13: 9781492103851

Publisher: Grand Valley State University

Language: English

## Conditions of Use

Attribution-NonCommercial-ShareAlike

CC BY-NC-SA

## Reviews

An introduction to proofs, or "bridge" course, provides a chicken-and-egg dilemma. Do you first lay the groundwork for logic, proofs, and writing and then subsequently use these for writing proofs in different mathematical contexts? Or, do you... read more

An introduction to proofs, or "bridge" course, provides a chicken-and-egg dilemma. Do you first lay the groundwork for logic, proofs, and writing and then subsequently use these for writing proofs in different mathematical contexts? Or, do you explore different mathematical contexts (e.g. number theory, combinatorics, geometry, calculus/analysis, algebra) as a means to motivate the foundations of mathematical logic, proofs, and writing? Neither can be done completely divorced from the other. Sundstrom's book takes the former approach with chapters on proofs, logic, writing, induction, set theory, functions, and relations that focus heavily on elementary number theory and particularly the notion of congruence. In these chapters, his text is appropriately comprehensive. These foundational chapters are followed by two further chapters on number theory and cardinality, providing some application of the preceding foundations. Other mathematical contexts are found in the exercises throughout. Users who desire the latter approach (using different mathematical areas to motivate the foundations) might find the text to be limited in its scope. However, users who prefer the approach taken here will find a comprehensive treatment appropriate for a one-semester bridge course.

This open textbook was formerly available as a traditional textbook from a traditional publisher (Pearson), and has been in use for nearly two decades. In addition, the author has numerous textbook credits with both traditional publishers and in open formats. Therefore, it is unsurprising that the accuracy is high.

The basic writing conventions and logical tools of theoretical mathematics change slowly over time, if at all. Thus, like in most mathematics texts, the contents of this book will remain relevant for beginning mathematics students for some time. Moreover, this textbook is structured with an active-learning pedagogy in mind. Given the growing preponderance of evidence for the efficacy of active learning in college mathematics instruction (e.g. https://www.pnas.org/content/111/23/8410), the pedagogical framework of this book should also remain relevant for years to come.

Bridge courses in mathematics exist for a reason. Many students find the transition from computationally-based mathematics (e.g. the calculus sequence) to theoretically-based mathematics (many upper-level electives) confusing to navigate. Clarity of thought and expression are essential to good mathematics, yet challenging to acquire for many. Moreover, improvement of thought and expression are two of the formational outcomes from studying mathematics. Thus, it is essential that a textbook resource for such a bridge course both be clear in its development and exposition, as well as teach these to students by more than merely example. Sundstrom's book is strong in this area. Not only is it lucid and readable, even for beginning undergraduates, it also tries to intentionally teach its readers the principles of the development of correct mathematical reasoning and the articulation of well-crafted arguments.

Similar to the question of accuracy, this book demonstrates the quality of its writing and editing through its consistency.

The book is divided into nine chapters, each of which is divided into 2-6 sections (excluding the chapter summaries). Each section is appropriate for 1-2 standard 50-minute class periods, depending upon the topic and the strength of the class. Thus, the text is readily divisible in a way that fits a standard semester schedule. Since mathematics, in general, builds upon itself in a more linear way than most disciplines, the book really isn't intended to be reorganized and realigned. It is unlikely that adopters will find this to be a deficiency given its context.

The textbook is well organized, and provides a clear and logical flow for a semester-long bridge course.

The text seems to be free of any interface issues. The bookmarks and hyperlinks in the pdf function correctly. There are very few figures, other than the occasional Venn diagram, graph, or table, and these all display nicely.

Again, this is a well-written and well-edited text without noticeable grammatical errors.

Unlike many texts in calculus, linear algebra, statistics, etc., a bridge course textbook provides little in the way of application, except to other areas of mathematics. In addition, most theoretical mathematics textbooks (although not all) are written in an academic tone, with very limited use of humor, colloquialisms, or cultural references. Given these things, the question of cultural sensitivity is essentially moot in this context. The prose is primarily in the first-person plural, using "we" throughout. There are a couple of examples that reference a named (hypothetical) person, although the names seem limited in their cultural diversity (e.g. "Ed" and "Laura").

The open version of this textbook was the inaugural winner of the Mathematical Association of America's Solow Award, the primary criterion for which is "... the material's impact on undergraduate education in mathematics and/or the mathematical sciences (operations research, statistics, computer science, applied mathematics)." Thus, it is clearly viewed within the mathematical community as being of high quality and having strong impact on student learning. This is no doubt due to the quality and clarity of the exposition, as well as its presumed active-learning approach. Almost every section begins with two Preview Activities, which are designed to be done by the students before they read the section (and before they have a classroom lesson on the topic). There are also occasional Progress Check activities within the sections that ask the reader to stop and determine if they are understanding the material. Each section includes a healthy, although not overwhelming, number of exercises. Finally, each chapter ends with a summary consisting of hyperlinked compendia of important definitions, results, and proof techniques. Although not officially part of the textbook itself, there are ancillary materials that help support teaching and learning with this textbook. The author has a web site devoted to this book that contains freely available resources (https://www.tedsundstrom.com/mathematical-reasoning-writing-and-proof). The author is also willing to send solutions to the Preview Activities and Exercises to adopters who request them via email. Finally, one of the author's colleagues at Grand Valley State University has put 107 screencasts on Youtube that are designed to support learning with this textbook (https://www.youtube.com/playlist?list=PL2419488168AE7001).

This text addresses most major components of proof methods, with suitable exploration exercises for the mathematical novice/undergraduate major which do not overly burden the reader with prerequisite knowledge. read more

This text addresses most major components of proof methods, with suitable exploration exercises for the mathematical novice/undergraduate major which do not overly burden the reader with prerequisite knowledge.

The book has accurate and only contains minimal typographical errors. The mathematics in the book is correct.

This text will be relevant for a long while. Students who become math or statistics majors need to understand proof, and the basic methods used in proof and mathematical logic have not significantly changed (and will not) over time.

This is a strong point of the text. The writing is extremely clear and simple, making it easy for the undergraduate reader to follow where ,any other books fail. The examples lead the reader gently towards an understanding of logic and proof. Especially good are the sections where the author clarifies how to write a proof for your audience.

Excellent. There are simply no problems with the consistency of the mathematical work or exposition.

This can generally be done, although it takes a bit of work. Mathematics courses are often linear in this way. Despite this, with a little extra effort by an instructor, most sections can be separated. For example, it is difficult to speak of correspondences without the notion of a function, but an instructor can simply introduce the function definition to address correspondences without covering the entire chapter on functions. (By the way, one of the topics covered is “modular” arithmetic, so I am inclined to say that those parts are quite modular!)

The presentation is clear and allows the instructor to develop a natural flow to a course.

There are no issues with the interface. It is an easy-to-read pdf, of small size.

The grammar is mostly good, with only a minor error or two: so minor that it is easy to not notice them.

This book is not culturally insensitive. It is simply mathematics, and doesn’t include any offensive content in the main chapters or exercises. I am rating this a 3 as it is therefore neutral in this regard.

This book is very useful either as a primary course text for an Introduction to Proof course, or as a supplementary text in a course in philosophical logic or mathematics content course at roughly the level of Calculus I or beyond.

## Table of Contents

- 1 Introduction to Writing Proofs in Mathematics
- 2 Logical Reasoning
- 3 Constructing and Writing Proofs in Mathematics
- 4 Mathematical Induction
- 5 Set Theory
- 6 Functions
- 7 Equivalence Relations
- 8 Topics in Number Theory
- 9 Finite and Infinite Sets
- A Guidelines for Writing Mathematical Proofs
- B Answers for the Progress Checks
- C Answers and Hints for Selected Exercises
- D List of Symbols
- Index

## About the Book

*Mathematical Reasoning: Writing and Proof*is designed to be a text for the ?rst course in the college mathematics curriculum that introduces students to the processes of constructing and writing proofs and focuses on the formal development of mathematics. The primary goals of the text are to help students:

- Develop logical thinking skills and to develop the ability to think more abstractly in a proof oriented setting.
- Develop the ability to construct and write mathematical proofs using standard methods of mathematical proof including direct proofs, proof by contradiction, mathematical induction, case analysis, and counterexamples.
- Develop the ability to read and understand written mathematical proofs.
- Develop talents for creative thinking and problem solving.
- Improve their quality of communication in mathematics. This includes improving writing techniques, reading comprehension, and oral communication in mathematics.
- Better understand the nature of mathematics and its language.

This text also provides students with material that will be needed for their further study of mathematics.

## About the Contributors

### Author

**Ted Sundstrom, **Professor of Mathematics, Grand Valley State University. PhD, (Mathematics), University of Massachusetts. Dissertation: Groups of Automorphisms of Simple Rings.