Misconceptions of the Limit Concept in a Mathematics Course for Engineering Students
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Nieuw Archief Voor Wiskunde
Nieuw Archief voor Wiskunde Boekbespreking Kevin Broughan Equivalents of the Riemann Hypothesis Volume 1: Arithmetic Equivalents Cambridge University Press, 2017 xx + 325 p., prijs £ 99.99 ISBN 9781107197046 Kevin Broughan Equivalents of the Riemann Hypothesis Volume 2: Analytic Equivalents Cambridge University Press, 2017 xix + 491 p., prijs £ 120.00 ISBN 9781107197121 Reviewed by Pieter Moree These two volumes give a survey of conjectures equivalent to the ber theorem says that r()x asymptotically behaves as xx/log . That Riemann Hypothesis (RH). The first volume deals largely with state- is a much weaker statement and is equivalent with there being no ments of an arithmetic nature, while the second part considers zeta zeros on the line v = 1. That there are no zeros with v > 1 is more analytic equivalents. a consequence of the prime product identity for g()s . The Riemann zeta function, is defined by It would go too far here to discuss all chapters and I will limit 3 myself to some chapters that are either close to my mathematical 1 (1) g()s = / s , expertise or those discussing some of the most famous RH equiv- n = 1 n alences. Most of the criteria have their own chapter devoted to with si=+v t a complex number having real part v > 1 . It is easily them, Chapter 10 has various criteria that are discussed more brief- seen to converge for such s. By analytic continuation the Riemann ly. A nice example is Redheffer’s criterion. It states that RH holds zeta function can be uniquely defined for all s ! 1. -
Calculus for the Life Sciences I Lecture Notes – Limits, Continuity, and the Derivative
Limits Continuity Derivative Calculus for the Life Sciences I Lecture Notes – Limits, Continuity, and the Derivative Joseph M. Mahaffy, [email protected] Department of Mathematics and Statistics Dynamical Systems Group Computational Sciences Research Center San Diego State University San Diego, CA 92182-7720 http://www-rohan.sdsu.edu/∼jmahaffy Spring 2013 Lecture Notes – Limits, Continuity, and the Deriv Joseph M. Mahaffy, [email protected] — (1/24) Limits Continuity Derivative Outline 1 Limits Definition Examples of Limit 2 Continuity Examples of Continuity 3 Derivative Examples of a derivative Lecture Notes – Limits, Continuity, and the Deriv Joseph M. Mahaffy, [email protected] — (2/24) Limits Definition Continuity Examples of Limit Derivative Introduction Limits are central to Calculus Lecture Notes – Limits, Continuity, and the Deriv Joseph M. Mahaffy, [email protected] — (3/24) Limits Definition Continuity Examples of Limit Derivative Introduction Limits are central to Calculus Present definitions of limits, continuity, and derivative Lecture Notes – Limits, Continuity, and the Deriv Joseph M. Mahaffy, [email protected] — (3/24) Limits Definition Continuity Examples of Limit Derivative Introduction Limits are central to Calculus Present definitions of limits, continuity, and derivative Sketch the formal mathematics for these definitions Lecture Notes – Limits, Continuity, and the Deriv Joseph M. Mahaffy, [email protected] — (3/24) Limits Definition Continuity Examples of Limit Derivative Introduction Limits -
The Modal Logic of Potential Infinity, with an Application to Free Choice
The Modal Logic of Potential Infinity, With an Application to Free Choice Sequences Dissertation Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Ethan Brauer, B.A. ∼6 6 Graduate Program in Philosophy The Ohio State University 2020 Dissertation Committee: Professor Stewart Shapiro, Co-adviser Professor Neil Tennant, Co-adviser Professor Chris Miller Professor Chris Pincock c Ethan Brauer, 2020 Abstract This dissertation is a study of potential infinity in mathematics and its contrast with actual infinity. Roughly, an actual infinity is a completed infinite totality. By contrast, a collection is potentially infinite when it is possible to expand it beyond any finite limit, despite not being a completed, actual infinite totality. The concept of potential infinity thus involves a notion of possibility. On this basis, recent progress has been made in giving an account of potential infinity using the resources of modal logic. Part I of this dissertation studies what the right modal logic is for reasoning about potential infinity. I begin Part I by rehearsing an argument|which is due to Linnebo and which I partially endorse|that the right modal logic is S4.2. Under this assumption, Linnebo has shown that a natural translation of non-modal first-order logic into modal first- order logic is sound and faithful. I argue that for the philosophical purposes at stake, the modal logic in question should be free and extend Linnebo's result to this setting. I then identify a limitation to the argument for S4.2 being the right modal logic for potential infinity. -
Hegel on Calculus
HISTORY OF PHILOSOPHY QUARTERLY Volume 34, Number 4, October 2017 HEGEL ON CALCULUS Ralph M. Kaufmann and Christopher Yeomans t is fair to say that Georg Wilhelm Friedrich Hegel’s philosophy of Imathematics and his interpretation of the calculus in particular have not been popular topics of conversation since the early part of the twenti- eth century. Changes in mathematics in the late nineteenth century, the new set-theoretical approach to understanding its foundations, and the rise of a sympathetic philosophical logic have all conspired to give prior philosophies of mathematics (including Hegel’s) the untimely appear- ance of naïveté. The common view was expressed by Bertrand Russell: The great [mathematicians] of the seventeenth and eighteenth cen- turies were so much impressed by the results of their new methods that they did not trouble to examine their foundations. Although their arguments were fallacious, a special Providence saw to it that their conclusions were more or less true. Hegel fastened upon the obscuri- ties in the foundations of mathematics, turned them into dialectical contradictions, and resolved them by nonsensical syntheses. .The resulting puzzles [of mathematics] were all cleared up during the nine- teenth century, not by heroic philosophical doctrines such as that of Kant or that of Hegel, but by patient attention to detail (1956, 368–69). Recently, however, interest in Hegel’s discussion of calculus has been awakened by an unlikely source: Gilles Deleuze. In particular, work by Simon Duffy and Henry Somers-Hall has demonstrated how close Deleuze and Hegel are in their treatment of the calculus as compared with most other philosophers of mathematics. -
Limits and Derivatives 2
57425_02_ch02_p089-099.qk 11/21/08 10:34 AM Page 89 FPO thomasmayerarchive.com Limits and Derivatives 2 In A Preview of Calculus (page 3) we saw how the idea of a limit underlies the various branches of calculus. Thus it is appropriate to begin our study of calculus by investigating limits and their properties. The special type of limit that is used to find tangents and velocities gives rise to the central idea in differential calcu- lus, the derivative. We see how derivatives can be interpreted as rates of change in various situations and learn how the derivative of a function gives information about the original function. 89 57425_02_ch02_p089-099.qk 11/21/08 10:35 AM Page 90 90 CHAPTER 2 LIMITS AND DERIVATIVES 2.1 The Tangent and Velocity Problems In this section we see how limits arise when we attempt to find the tangent to a curve or the velocity of an object. The Tangent Problem The word tangent is derived from the Latin word tangens, which means “touching.” Thus t a tangent to a curve is a line that touches the curve. In other words, a tangent line should have the same direction as the curve at the point of contact. How can this idea be made precise? For a circle we could simply follow Euclid and say that a tangent is a line that intersects the circle once and only once, as in Figure 1(a). For more complicated curves this defini- tion is inadequate. Figure l(b) shows two lines and tl passing through a point P on a curve (a) C. -
Limits of Functions
Chapter 2 Limits of Functions In this chapter, we define limits of functions and describe some of their properties. 2.1. Limits We begin with the ϵ-δ definition of the limit of a function. Definition 2.1. Let f : A ! R, where A ⊂ R, and suppose that c 2 R is an accumulation point of A. Then lim f(x) = L x!c if for every ϵ > 0 there exists a δ > 0 such that 0 < jx − cj < δ and x 2 A implies that jf(x) − Lj < ϵ. We also denote limits by the `arrow' notation f(x) ! L as x ! c, and often leave it to be implicitly understood that x 2 A is restricted to the domain of f. Note that we exclude x = c, so the function need not be defined at c for the limit as x ! c to exist. Also note that it follows directly from the definition that lim f(x) = L if and only if lim jf(x) − Lj = 0: x!c x!c Example 2.2. Let A = [0; 1) n f9g and define f : A ! R by x − 9 f(x) = p : x − 3 We claim that lim f(x) = 6: x!9 To prove this, let ϵ >p 0 be given. For x 2 A, we have from the difference of two squares that f(x) = x + 3, and p x − 9 1 jf(x) − 6j = x − 3 = p ≤ jx − 9j: x + 3 3 Thus, if δ = 3ϵ, then jx − 9j < δ and x 2 A implies that jf(x) − 6j < ϵ. -
MATH M25BH: Honors: Calculus with Analytic Geometry II 1
MATH M25BH: Honors: Calculus with Analytic Geometry II 1 MATH M25BH: HONORS: CALCULUS WITH ANALYTIC GEOMETRY II Originator brendan_purdy Co-Contributor(s) Name(s) Abramoff, Phillip (pabramoff) Butler, Renee (dbutler) Balas, Kevin (kbalas) Enriquez, Marcos (menriquez) College Moorpark College Attach Support Documentation (as needed) Honors M25BH.pdf MATH M25BH_state approval letter_CCC000621759.pdf Discipline (CB01A) MATH - Mathematics Course Number (CB01B) M25BH Course Title (CB02) Honors: Calculus with Analytic Geometry II Banner/Short Title Honors: Calc/Analy Geometry II Credit Type Credit Start Term Fall 2021 Catalog Course Description Reviews integration. Covers area, volume, arc length, surface area, centers of mass, physics applications, techniques of integration, improper integrals, sequences, series, Taylor’s Theorem, parametric equations, polar coordinates, and conic sections with translations. Honors work challenges students to be more analytical and creative through expanded assignments and enrichment opportunities. Additional Catalog Notes Course Credit Limitations: 1. Credit will not be awarded for both the honors and regular versions of a course. Credit will be awarded only for the first course completed with a grade of "C" or better or "P". Honors Program requires a letter grade. 2. MATH M16B and MATH M25B or MATH M25BH combined: maximum one course for transfer credit. Taxonomy of Programs (TOP) Code (CB03) 1701.00 - Mathematics, General Course Credit Status (CB04) D (Credit - Degree Applicable) Course Transfer Status (CB05) -
Sequences and Their Limits
Sequences and their limits c Frank Zorzitto, Faculty of Mathematics University of Waterloo The limit idea For the purposes of calculus, a sequence is simply a list of numbers x1; x2; x3; : : : ; xn;::: that goes on indefinitely. The numbers in the sequence are usually called terms, so that x1 is the first term, x2 is the second term, and the entry xn in the general nth position is the nth term, naturally. The subscript n = 1; 2; 3;::: that marks the position of the terms will sometimes be called the index. We shall deal only with real sequences, namely those whose terms are real numbers. Here are some examples of sequences. • the sequence of positive integers: 1; 2; 3; : : : ; n; : : : • the sequence of primes in their natural order: 2; 3; 5; 7; 11; ::: • the decimal sequence that estimates 1=3: :3;:33;:333;:3333;:33333;::: • a binary sequence: 0; 1; 0; 1; 0; 1;::: • the zero sequence: 0; 0; 0; 0;::: • a geometric sequence: 1; r; r2; r3; : : : ; rn;::: 1 −1 1 (−1)n • a sequence that alternates in sign: 2 ; 3 ; 4 ;:::; n ;::: • a constant sequence: −5; −5; −5; −5; −5;::: 1 2 3 4 n • an increasing sequence: 2 ; 3 ; 4 ; 5 :::; n+1 ;::: 1 1 1 1 • a decreasing sequence: 1; 2 ; 3 ; 4 ;:::; n ;::: 3 2 4 3 5 4 n+1 n • a sequence used to estimate e: ( 2 ) ; ( 3 ) ; ( 4 ) :::; ( n ) ::: 1 • a seemingly random sequence: sin 1; sin 2; sin 3;:::; sin n; : : : • the sequence of decimals that approximates π: 3; 3:1; 3:14; 3:141; 3:1415; 3:14159; 3:141592; 3:1415926; 3:14159265;::: • a sequence that lists all fractions between 0 and 1, written in their lowest form, in groups of increasing denominator with increasing numerator in each group: 1 1 2 1 3 1 2 3 4 1 5 1 2 3 4 5 6 1 3 5 7 1 2 4 5 ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;::: 2 3 3 4 4 5 5 5 5 6 6 7 7 7 7 7 7 8 8 8 8 9 9 9 9 It is plain to see that the possibilities for sequences are endless. -
Mathematics for Economics Anthony Tay 7. Limits of a Function The
Mathematics for Economics Anthony Tay 7. Limits of a function The concept of a limit of a function is one of the most important in mathematics. Many key concepts are defined in terms of limits (e.g., derivatives and continuity). The primary objective of this section is to help you acquire a firm intuitive understanding of the concept. Roughly speaking, the limit concept is concerned with the behavior of a function f around a certain point (say a ) rather than with the value fa() of the function at that point. The question is: what happens to the value of fx() when x gets closer and closer to a (without ever reaching a )? ln x Example 7.1 Take the function fx()= . 5 x2 −1 4 This function is not defined at the point x =1, because = 3 the denominator at x 1 is zero. However, as x f(x) = ln(x) / (x2-1) 1 2 ‘tends’ to 1, the value of the function ‘tends’ to 2 . We 1 say that “the limit of the function fx() is 2 as x 1 approaches 1, or 0 0 0.5 1 1.5 2 lnx 1 lim = x→1 x2 −1 2 It is important to be clear: the limit of a function and the value of a function are two completely different concepts. In example 7.1, for instance, the value of fx() at x =1 does not even exist; the function is undefined there. However, the limit as x →1 does exist: the value of the function fx() does tend to 1 something (in this case: 2 ) as x gets closer and closer to 1. -
Maximum and Minimum Definition
Maximum and Minimum Definition: Definition: Let f be defined in an interval I. For all x, y in the interval I. If f(x) < f(y) whenever x < y then we say f is increasing in the interval I. If f(x) > f(y) whenever x < y then we say f is decreasing in the interval I. Graphically, a function is increasing if its graph goes uphill when x moves from left to right; and if the function is decresing then its graph goes downhill when x moves from left to right. Notice that a function may be increasing in part of its domain while decreasing in some other parts of its domain. For example, consider f(x) = x2. Notice that the graph of f goes downhill before x = 0 and it goes uphill after x = 0. So f(x) = x2 is decreasing on the interval (−∞; 0) and increasing on the interval (0; 1). Consider f(x) = sin x. π π 3π 5π 7π 9π f is increasing on the intervals (− 2 ; 2 ), ( 2 ; 2 ), ( 2 ; 2 )...etc, while it is de- π 3π 5π 7π 9π 11π creasing on the intervals ( 2 ; 2 ), ( 2 ; 2 ), ( 2 ; 2 )...etc. In general, f = sin x is (2n+1)π (2n+3)π increasing on any interval of the form ( 2 ; 2 ), where n is an odd integer. (2m+1)π (2m+3)π f(x) = sin x is decreasing on any interval of the form ( 2 ; 2 ), where m is an even integer. What about a constant function? Is a constant function an increasing function or decreasing function? Well, it is like asking when you walking on a flat road, as you going uphill or downhill? From our definition, a constant function is neither increasing nor decreasing. -
CHAPTER 2: Limits and Continuity
CHAPTER 2: Limits and Continuity 2.1: An Introduction to Limits 2.2: Properties of Limits 2.3: Limits and Infinity I: Horizontal Asymptotes (HAs) 2.4: Limits and Infinity II: Vertical Asymptotes (VAs) 2.5: The Indeterminate Forms 0/0 and / 2.6: The Squeeze (Sandwich) Theorem 2.7: Precise Definitions of Limits 2.8: Continuity • The conventional approach to calculus is founded on limits. • In this chapter, we will develop the concept of a limit by example. • Properties of limits will be established along the way. • We will use limits to analyze asymptotic behaviors of functions and their graphs. • Limits will be formally defined near the end of the chapter. • Continuity of a function (at a point and on an interval) will be defined using limits. (Section 2.1: An Introduction to Limits) 2.1.1 SECTION 2.1: AN INTRODUCTION TO LIMITS LEARNING OBJECTIVES • Understand the concept of (and notation for) a limit of a rational function at a point in its domain, and understand that “limits are local.” • Evaluate such limits. • Distinguish between one-sided (left-hand and right-hand) limits and two-sided limits and what it means for such limits to exist. • Use numerical / tabular methods to guess at limit values. • Distinguish between limit values and function values at a point. • Understand the use of neighborhoods and punctured neighborhoods in the evaluation of one-sided and two-sided limits. • Evaluate some limits involving piecewise-defined functions. PART A: THE LIMIT OF A FUNCTION AT A POINT Our study of calculus begins with an understanding of the expression lim fx(), x a where a is a real number (in short, a ) and f is a function. -
Basic Analysis I: Introduction to Real Analysis, Volume I
Basic Analysis I Introduction to Real Analysis, Volume I by Jiríˇ Lebl June 8, 2021 (version 5.4) 2 Typeset in LATEX. Copyright ©2009–2021 Jiríˇ Lebl This work is dual licensed under the Creative Commons Attribution-Noncommercial-Share Alike 4.0 International License and the Creative Commons Attribution-Share Alike 4.0 International License. To view a copy of these licenses, visit https://creativecommons.org/licenses/ by-nc-sa/4.0/ or https://creativecommons.org/licenses/by-sa/4.0/ or send a letter to Creative Commons PO Box 1866, Mountain View, CA 94042, USA. You can use, print, duplicate, share this book as much as you want. You can base your own notes on it and reuse parts if you keep the license the same. You can assume the license is either the CC-BY-NC-SA or CC-BY-SA, whichever is compatible with what you wish to do, your derivative works must use at least one of the licenses. Derivative works must be prominently marked as such. During the writing of this book, the author was in part supported by NSF grants DMS-0900885 and DMS-1362337. The date is the main identifier of version. The major version / edition number is raised only if there have been substantial changes. Each volume has its own version number. Edition number started at 4, that is, version 4.0, as it was not kept track of before. See https://www.jirka.org/ra/ for more information (including contact information, possible updates and errata). The LATEX source for the book is available for possible modification and customization at github: https://github.com/jirilebl/ra Contents Introduction 5 0.1 About this book ....................................5 0.2 About analysis ....................................7 0.3 Basic set theory ....................................8 1 Real Numbers 21 1.1 Basic properties ...................................