May 31, 2010
| 1. Euclidean Algorithm (old animation) | 2. Euclidean Algorithm 2 (new) | 3. Arithmetic |
| 4. Axiomatics | 5. Axiomatics 2 | 6. |
| 7. Zeno_1 | 8. | 9. |
| 10. Number Line | 11. Ratios_3 (Descartes) | 12. Dienes Blocks |
| 13. Nested_Intervals | 14. Dienes Multiplication | 15. Dienes Blocks 2 |
| 16. Secant | 17. | 18. |
| 19. Integration 1 | 20. Integration 2 | 21. Limit 1 |
| 23. Irrationals | 24.Integration 3 | |
| 25. Fourier Formula | 26. Fourier 2 | 27. Symbols |
| 28. Fourier 3 | 29. Zarlino | |
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Not immediately needed | ||
| 1. Bolzano_Theorem | 2. Cantor | 3. Conics |
| 4. Complex Numbers | 5. Courant Calculus 406 | 6 Fundamental Calculus |
| 7. Linkage Experiment | 8. Maxima and Minima | 9. Uses of Integration |
This page has been based on the following book because one of its authors was at the center of things when much of the modern scientific view and mathematical curriculum was being structured in Berlin and Gottingen and further, he made a very determined and committed effort to explain it all in my own native language, English, as best it could be done. I have used it as the foundation for my own math studies but will now edit the page a bit and limit it to a more specific understandicng of math as it can be clearly related to the guitar. And bring in a some more recent internet material as well.
Courant RobbinsWhat is Mathematics ? |
By Richard Courant, Herbert Robbins, Revised - Ian Stewart |
1996, Oxford University Press Originally Published - 1941 |
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Richard Courant's qualifications may best be derived from this interview: http://www.aip.org/history/ohilist/4562.html - so far as I can tell he was highly influential in establishing at least some of the standard calculus curriculum. For me, the immediate objective is a calculus animation sufficient to explain guitar harmonics to a somewhat less than mathematically inclined musician yet rigorous enough to satisfy a Calculus I teacher; and to align the project with the following statement from Courant Robbins:
I don't need the whole of mathematics, just what can be clearly related to the guitar The notes on the first 400 pages are to help me deal with some background material and inadequacies in my math. Those marked in red are thought to be most important for me. | |
| p 1 - Mathematical statements should be reducible to statements about the natural numbers | A preliminary sketch - Arithmetic. To be developed further. |
| 11 - mathematical induction (Mathematical proof) | (paraphrasing -Proof by mathematical induction is based on the concept that any integer may be reached by a sequence of steps in which 'after any integer (r), there is a next (r+1)' |
| p 14 Sum of the First n squares - interesting application of mathematical induction |
Sum of the First n Squares animation It is used in the introduction to integration on page 408. |
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| p 15 - | The formal logical proof does not show how it was discovered. Discovery requires creative choice, experiment, analogy, and something CourantRobbins calls "constructive intuition". |
| p 21 | - most mathematical statements concern classes of objects that have a common property |
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Euclidean Algorithm |
see p. 236 (margin note - prob. looked up "algorithm" online) re: Mathematical Rigor - amenability to algorithm checking (Wikipedia - ...completely rigorous proofs which tend to be (long and unwieldly) may obscure what is being demonstrated.) |
| p 52 - reduce measuring to counting | |
| p 54,55 |
...guided by the need for a suitable instrument for handling measurements... The rules for operating with new numbers (rationals, irrationals,transcendentals etc..) ... are created by us ...to preserve the fundamental laws of arithmetic. p89...extended number domain...freely created by definition...but useless (unless the prevailing rules and properties of the original domain are preserved in the larger domain) |
| p 57 - Geometric Interpretation of Rational
Numbers |
(Monochord string might serve as a number axis - idea of infinite division of a continuum in a limited segment) see numberLine.html |
| p 58 - Incommensurable Segments, Irrational Numbers, Concept of Limit |
(Given b = Pi(a) |
| b = (m/n)(a) commensurable because they have a
common measure a/n which goes: n times into a m times into b |
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| p 60 - | (...irrational numbers are needed to keep... mutual correspondence between numbers... and points on a straight line...) |
| ...an irrational number represents the length of a segment incommensurable with the unit. | |
| p 62 - (sqRt 2) - indefinite extended decimal fraction... | ... no known formula to determine the successive digits |
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p 63 Introduction to limit concept "...it sometimes happens that a certain rational number s is approximated by a sequence of other rational numbers s sub n, where the index n assumes consecutively all the values 1, 2, 3..."
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...described as an intuitive introduction preliminary to discussing the number continuum; a more thorough discussion of limit concept starts at p 289 where "limit of a squence" is used - |
| p 64 The infinite enters only in the unending 'proceedure' and not as an actual quantity. | see p 289 - 305 |
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p 68-69 - ... nested intervals - fundamental postulate of geometry. p 68 "...the continuum of numbers or real number system...is the totality of infinite decimals. Finite decimals may be considered a special case where all digits from a certain point on are zero..." |
nested_intervals.html http://everything2.com
A Radical Approach to Real Analysis
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| p 69 - all the mathematical properties of irrational points may be expressed as properties of nested sequences of rational intervals. | |
| p 70 - Nested Intervals | (...only the properties and relations of mathematical objects are relevent...) |
| p 70 | ( the mathematical laws of rational numbers(addition, subtraction, etc and < [less than] and >[greater than]) are preserved for irrational numbers defined as nested sequences of rational intervals) |
| p 71 - . | ... the number continuum is the basis of the limit concept... |
| p 72 - Cantor's definition of the continuum: | |
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starting with: Cantor; Convergence is understood to mean that the difference (a sub m - a sub n) between any two numbers of the sequence tends to zero when (a sub m) and (a sub n) are sufficiently far out in the sequence, as m and n tend to infinity. |
flash movie Cantor |
| p 72 the number continuum... has been the basis of mathematics and in particular of analytic geometry and the calculus - since the seventeenth century... | |
| p 73 - ...every geometrical object and every geometrical operation can be referred to the realm of numbers. | |
| p 73 - The fundamental idea of analytic geometry is ... numbers attached to or coordinated with a geometrical object and characterizing this object completely. | |
| p 74 - Equations of Lines and Curves [ |
continuation of Analytic Geometry - needs a couple of animations and probably some external links.] |
| p 76 - . |
September 30, 2008 - Algebra (in general, not treated as a specific topic in courantRobbins) http://en.wikipedia.org/wiki/Algebra
*** http://abstractmath.org Mathematical Structure |
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Mathematical Analysis of Infinity p 77 - ... the concept of the infinite pervades all of mathematics since mathematical objects are usually studied not as individuals but as members of classes or aggregates containing infinitely many objects of the same type. |
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p 78 - (RE: Cantor's general concept of a set or aggregate) ...any collection of objects defined by some rule which specifies exactly which objects belong to the given collection... *** ...if the elements in two sets A & B may be paired with each other...so that: "to each element of A there corresponds one and only only one element of B" and "to each element of B corresponds one and only one element of A" then the correspondence is said to be "biunique" and A is said to be equivalent.
This is in fact the very idea of counting, for when we count a finite set of objects, we simply establish a biunique correspondence between these objects and a set of number number symbols 1,2,3,... [ror-keeping in mind some ultimate purpose that - (p 1 - Mathematical
statements should be reducible to statements about the natural
numbers)
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Sets and Number Line (first entered September 30, 2008 - October 6, 2008 - An animation Axiomatics has been started.) see also p 108 some external references: http://en.wikibooks.org/
***
*** http://www.webmath.com/k8numlinecomp.html
*** http://en.wikipedia.org/wiki/Set_theory
*** http://en.wikipedia.org/
*** October 30, 2008 - The following seems useful:
p57 Cantor's Set Theory ...When mathematicians define some abstract mathematical object or system as a 'set of objects' satisfying certain properties, it usually does not matter what the members of the set are; rather, what counts are the operations that can be performed on those members. in fact, even that is not quite right. The real interest is in the properties of those operations... (i.e. if studying natural numbers: Their interest is in the various properties of numbers and of the operations of arithmetic, properties such as the commutativeity of addition, whether one number divides evenly into another, whether a number is prime,and so forth. http://www.stanford.edu/~kdevlin/Math_in_2100.pdf What will count as mathematics in 2100? p2 After Newton and Leibniz, mathematics became the study of number, shape, motion, and change.... In the middle of the 19thcentury, however, a revolution took place. Generally regarded as having its epicenter in the small university town of Göttingen in Germany, the revolution’s leaders were the mathematicians Lejeune Dirichlet, Richard Dedekind, ...and Bernhard Riemann. -------------------------------------------------------------------------------- ...In their new conception of the subject, the primary focus was not performing a calculation or computing an answer, but formulating and understanding abstract concepts and relationships...Mathematical objects, which had been thought of as given primarily by formulas, came to be viewed rather as carriers of conceptual properties. Proving was no longer a matter of transforming terms in accordance with rules, but a process of logical deduction from concepts. In the 1980s, however, a definition of mathematics emerged... mathematics is the science of patterns. Those patterns can be either real or imagined, visual or mental, static or dynamic,qualitative or quantitative, purely utilitarian or of little more than recreational interest. They can arise from the world around us, from the depths of space and time, or from the inner workings of the human mind. (ror- caveat, people will create patterns out of noise, ie constellations, )
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p88 - (Foundations of Mathematics) ...(continuum hypothesis - reduces to questions of what is meant by mathematical existence. "Luckily, the existence of mathematics does not depend on a satisfactory answer...intuition always remains the vital element...") |
http://en.wikipedia.org/ |
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p 88-93 - Imaginary Numbers
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August 4, 2008 February 20, 2009 - p.92 Art 2 - Geometrical Interpretation of Complex Numbers - browsing, reread and noted "utmost" - last sentence...(the geometrical approach is unnecessary to mathamatics based on the formal definitions of addition and multiplication [more or less Axiomatic Set Theory] - but "of the utmost importance" (in applications and physics)). August 15 - might want to add following from p 89... the imaginary unit has nothing to do with counting...it is merely a symbol subject to the fundamental rule i^2 = -1...its value will depend entirely on whether by this introduction a really useful and workable extension of the number system can be effected.
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| p 98 - roots of unity?? | |
| p 101 - The Fundamental Theorem of
Algebra (it should more fittingly be called) the fundamental
theorem of the complex number system)
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p 103 - The concept of algebraic number is a natural generalization of rational number, which constitutes the special case when n =1. Not every real number is algebraic. This may be shown by a proof due to Cantor, that the totality of all algebraic numbers is denumerable. Since the set of all real numbers is non-denumerable, there must exist real numbers which are not algebraic. |
(January 22, 2010 - all this has become interesting, very interesting actually, but it will all have to wait untill it arises in the natural course of algebra studies which I will return to after this Fourier animation on February 1 The Fourier will be an outline,a sketch to inform the limited mathematical studies I wish to undertake, those studies are expected to allow a reasonably good completed Fourier in about 6 monmths-1 year. The fact is, Fourier requires calculus and calculus, even for my limited purposes requires algebra and function experience, skill.) |
| p 108 - The Algebra of Sets - ... sets may be
combined by certain operations to form other sets. |
Set theory is a distinctly weak part of my math background. The articles here refer to "multiplication is not repeated addition" have not led me to any conclusions, perhaps some cautions: ...September 18,2008 - just completed a review of Devlin's second
article: Apparently he wants the principles of axiomatic set theory and arithmetic operations not contradicted (by statements like ""multiplication is repeated addition)- and he wants the teachers to decide how to do it themselves. - it was all very contentious and I have never made much out of it except for the idea of multiplication as proportion noted in several articals below. "As I said earlier, I don't think it would be a sensible thing to teach arithmetic by starting with the real number system; indeed, I find it hard to imagine how that could possibly succeed. But since that is the culmination of the arithmetic learning journey, it would be wise to avoid doing anything that runs counter to that final goal system." Courant Robbins makes this point at page 70; "Some modern textbooks on mathematics repel many students by starting with a pedantically complete analysis of the real number system." (More or less what actually happened during the New Math episode.) *** For a sympathetic argument: a detailed discussion of "The New Math" and plea for saving what was good. http://lsc-net.terc.edu/ *** As to multiplication not being repeate addition: http://www.themathpage.com/ARITH/ Here is the most general definition of multiplication: Whatever ratio the multiplier has to 1 Consider this multiplication of whole numbers: 3 × 8 = 24 The multiplier 3 is three times 1; therefore the product will be three times the multiplicand; it will be three times 8. (ror 3:1::24:8) *** October 6-7, 2008 - An animation Axiomatics has been started to help me work out some of this. December 11, 2008 - A set theoretic derivation of multiplication seems unlikely (for me - very) in the near future. For the time being I am keeping a proportional understanding of the operation, as follows. http://cehd.umn.edu TEACHERS' SOLUTIONS FOR MULTIPLICATIVE PROBLEMS ...the ratio and proportion solutions are based on relational, genuine understanding of the problem situation http://www.wtamu.edu/
academic/anns/mps/math/ http://www.wtamu.edu/academic/anns/mps/math/ West Texas A&M University (WTAMU). Kim Seward with the assistance of Jennifer Puckett.... created as a service to anyone who needs help in these areas of math. Last revised on Jan. 8, 2002 Also: http://www.ltcconline.net/ and: http://www2.dsu.nodak.edu/users/ and: http://mathforum.org/library
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p112 - ...the laws 1-26 form the basis of the algebra of sets...
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September 22, 2008 - The following puts some perspective on Sets for me: http://en.wikipedia.org/ The modern study of set theory was initiated by Cantor and Dedekind in the 1870s. After the discovery of paradoxes in informal set theory, numerous axiom systems were proposed in the early twentieth century, of which the Zermelo–Fraenkel axioms, with the axiom of choice, are the most well known. Set theory, formalized using first-order logic, is the most common foundational system for mathematics. The language of set theory is used in the definitions of nearly all mathematical objects..." ...properties of the natural and real numbers can be derived within set theory, as each number system can be identified with a set of equivalence classes under a suitable equivalence relation whose field is some infinite set.
This site provided some terminology http://en.wikibooks.org/ and this quote from it seems helpful: "The objective of algebra is often to take the information available in a situation or problem, and to define or determine a set of elements such as numbers as simply and precisely as possible." |
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p 112 - ...use the laws 1-26 as the basis for an "algebra of logic"
The rules for translating the usual logical terminology into the
language of sets ... |
[...written I believe, before any real computers existed...needs googling, verification & updating...symbols probably, if not the logic...] *** From an even older source, a logician and mathematical historian: Jourdaine, Philip E. B., The Nature of Mathematics, in: Newman, The World of Mathematics Vol I p 4, Simon and Schuster, New York, 1956
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p 120 - 121 (...understanding lies in translating the geometrical problems into the language of algebra...
It is the principle of analytic geometry, the quantitative characterization of geometrical objects by real numbers, based on the introduction of the real number continuum, that provides the foundation for the whole theory. |
December 11. 2008 Abraham Kaplan cited in Newman, The World of Mathematics, Vol 2, p1297 Simon and Schuster, 1956
Courant Robbins continues with some illustrations and explanations pretty much directly from Descartes, La Geometrie and I have already related some of this to music (cf w/ Zarlino's mesolabium, Descarte's Proportional Compass - (Origins 2, 3 animations) |
| p 141 - By a transformation or mapping of the plane onto itself we mean a rule which assigns to every point P of the plane another point P' called the image of P under the transformation. | |
| p 147 - Fig. 46 - Mechanical device for doubling
the cube |
(cf w/ Zarlino's mesolabium, Descarte's Proportional Compass - (Origins 2, 3 animations) |
| p 156 - Fig. 55 - Peaucellier's linkage transforming rotation into rectilinear motion. | [pp147-156 may be useful in Mesolabium Linkage , Origins2-3 animations] |
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p 181 - ( Logically [a geometrical object] ) is completely described by the totality of statements by which it is related to other [geometrical] statements...) [...ordinary axioms of geometry(Euclid's) objects are abstractions from the physical world of ...chalk, stretched strings, light rays...etc... "Geometrical [objects] have essentially simpler properties than do any physical objects, and this simplification provides the essential condition for the development of geometry as a deductive science." |
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p 214 - Axiomatic Method |
October 6-7, 2008 - Animation Axiomatics started. *** http://en.wikipedia.org/wiki/Axiom
***
Good treatment of conics: Also, some time ago I had some historical connections of Descartes >
Papus > Conics > Locus of Three or Four Lines > Calculus - now
lost, here is a historical treatment of conics: |
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p 214 - The Axiomatic Method - ...each theorem of the system is proved by showing it is a necessary logical consequence of some previously proved proposition... (As a starting point), there must be some statements, called postulates or axioms which are accepted as true, and for which proof is not required... |
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p 215 - (to be of value, the axioms must be): 1. simple and it is also desirable that the axioms are 5. independent (no one of them is a logical consequence of the others.) |
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p 215 - Differing philosophies on the "Foundations of Mathematics" Intuitionists (Kantian) - mathematical entities are considered to exist in a realm of "pure intuition", independent of definitions...does not accept the number continuum, admits the denumerably infinite...(clarify???) Formalists - concern is only with the formal logical proceedure of reasoning on the basis of postulates...(accepts the number continuum)...grants all the freedom necessary for theory and applications...but...imposes the necessity of proving that these axioms, accepted as arbitrary creations of the human mind, cannot possibly lead to contradictions...(per Godel etc...it appears that proofs for consistency and completeness are not possible within strictly closed systems of concepts.) |
Rigorous adherance to a philosophical point of view sharpens the debate and narrows the issues however, citing and paraphrasing John von Neumann, (this controversy) "...constitutes the best caution against taking the immovable rigor of mathematics too much for granted... and I know myself how humiliatingly easily my own views regarding the absolute mathematical truth changed during this episode, and how they changed three times in succession." Newman, World of Mathematics, Vol 4, p 2059 For myself, I find philospophy fun but am more concerned with the bottleneck of a "Pons Assinorum" too narrow for the times and the numbers that must cross if there is to be any safety factor to existence on so small a lifeboat as this planet now affords so large a population. I am a big fan of safety factors since loading a tank on the deck of a Victory ship with a rather neglected jumbo boom back in 1968 or so. Those who had done the calculations did not do the loading. It was a success, perhaps the tank is still being usefully employed by those it was intended to shoot, and luck is good, sometimes it is all that is available, likely more of it will be available if it is not the only thing relied upon. |
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p 216 - (regardless of the philosophy)...The axiomatic approach to a mathematical subject is the natural way to unravel the network of connections between the various facts and to exhibit the essential logical skeleton of the structure. ....but a significant discovery or insight is rarely obtained by an exclusively axiomatic proceedure...The constructive intuition of the mathematician brings to mathematics a non-deductive and irrational element which makes it comparable to music and art |
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p 217-The totality of axioms of geometry provides the implicit definition of all "undefined" geometrical terms... if the formal axioms did not agree more or less with the properties of physical objects, then geometry would be of little interest...(this) decides the direction of mathematical thought. |
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| p 221 - A satisfactory proof of the consistancy of the axioms of Euclidean geometry has never been given, except by referring it back to the concepts of analytic geometry and hence ultimately to the number continuum, whose consistancy is again an open question. |
number continuum see numberLine.html |
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p 222 - ...the base chosen for the logarithm is of no importance, since
change of base merely changes the unit of measurement. [section dealing
with non-euclidean distance] log a + log b = log (ab) (Intuitively, this formula could be obtained by looking at the areas defining the three quantities log a, log b, and log (ab)] [p 442 ...the basic concepts of the calculus furnish a much more adequate theory of the logarithms and the exponential function than (the usual school instruction)...] |
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| p 223 - "The revolutionary importance of the discovery of non-Euclidean geometry lay in the fact that it demolished the notion of the axioms of Euclid as the immutable mathematical framework into which our experimental knowledge of physical reality must be fitted." | |
| p 236 - "Since the ideal of perfect rigor is neither necessary nor desirable during one's first steps in an unfamiliar field, we shall not hesitate from time to time to appeal to the reader's geometrical intuition." |
An important point for me - When something is placed on the world wide web a range of viwers from beginner to expert might profitably be taken into account... http://www.maths.uwa.edu.au/~schultz Richard Dedekind "Even now such resort to geometric intuition in a first presentation of the differential calculus, I regard as exceedingly useful, from the didactic standpoint, and indeed indispensable, if one does not wish to lose too much time. But that this form of introduction into the differential calculus can make no claim to being scientific, no one will deny." *** (ror - another idea belongs here, source missing, paraphrased to the effect 'a rigorous treatment, by reason of its considerable detail, tends to obscure rather than demonstrate the conceptual treatment.'') |
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p 272 - Functions and Limits The main body of modern mathematics centers around the concepts of functions and limits.. |
Of critical importance - for me; need a more complete understanding in relation to the later chapters on Calculus |
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p 272 - The concept of function enters whenever quantities are connected by a definite physical relationship...The whole domain of periodic phenomena - the motion of tides, the vibrations of a plucked string, the emission of light waves from an incandescent filament - is governed by the simple trigonometric functions sin x and cos x. (check the above, somewhere in the book a distinction between a function in physics and one in mathematics is noted) |
plucked string |
| p 273 - (...up to the 19th century...) the idea a functional relationship was more or less identified with the existence of a simple mathematical formula expressing the exact nature of the relationship. This concept proved too narrow... | |
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p 276 - A mathematical function is simply a law governing the interdependence of varying quantities. It does not imply the existence of any relationship of "cause and effect" between them... It is only the form of the connection between the...variables which is relevant to the mathematician. |
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| p 283 - ...roughly speaking, we say that a function is continuous if its graph is a smooth, uninterrupted curve. | |
| p 286 - In the same way that a graph gives a geometrical representation of a function of one variable, a geometrical representation of a function u = f(x,y) of two variables is afforded by a surface in the three-dimensional space with x,y,u as coordinates. | |
| p 287 - Functions of several variables occur in physics when the motion of a continuous substance is to be described..(when a plucked string is released)...it will vibrate in such a way that the particle with the original coordinate x will have at the time t a distance u = f(x,t) from the x-axis. The motion is completely described as soon as the function u = f(x, t) is known |
(?- Fourier analysis IS the function u = f(x, t)?) plucked string |
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p 289 - ...the description of the continuity of a function is based on the limit concept. p291...epsilonDelta concept of limit (geometric series) |
(...limit of a sequence here is just an introduction to the concept of limit ?] see p 63 see p 303 November 14, 2008 There is now an animation, Limit 1; today it is just links to the youTube videos I find useful but It may be expanded a bit later. The non-video pages being looked at: http://www.themathpage.com/
There are some epsilon delta applets - Limit Concept http://www.slu.edu http://math.hws.edu (July 21,2008 - currently thinking of a variation of Equal Temperament 1 and 2 animations, but single animation, both number line and sequence sideBySide - vague at this moment - will have to be much shorter and very clear to be worthwhile... |
| p 292 (limit of a sequence, epsilonDelta, and snobish textbook writers) |
December 11, 2008 - I have been reading this page and will reread, so far there appears little danger of comprehension. I am interested in possibly starting with some variation of the phrase near the bottom of the page: "...we must base our definition (of limit) on what we have to do if we wish actually to check the statement a(sub n) --> a." It seems the most readily comprehensible part of the explanation, necessary and reasonable and leads me into the discussion rather than chasing me away from it. (Also, I would like to find some reason beyond a test score as to why anyone should go to the trouble to learn so convoluted an explanation. I have studied (and written) rather equally difficult things in the practice of law but usually for the purpose of confusing rather than clarifying an issue) Possibly from quantum mechanics and the uncertainty principle which apparently post-date the explanation but may justify it: Erwin Schrodinger, Causality and Wave Mechanics, cited in Newman, World of Mathematics, Vol 2, p 1057, 1056 - "Observations are to be regarded as discrete, disconnected events. Between them there are gaps which we cannot fill in."... no model shaped after our large-scale experiences can ever be true...however we think it, it is wrong." Niels Bohr and Courant had been caballing on such ideas for many years and despite its paradoxes it is rather successful. It would provide a good reason to work through this. A good test score is inadequate save for those who can't get anything other than a good score, whatever the reason ) |
| p 296 - ...any irrational number (such as sqrt2) is the limit of the monotone increasing and bounded sequence of rational decimal fractions obtained by breaking off an infinite decimal at the nth digit | |
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p 297 - The importance of the limit concept in mathematics lies in the fact that many numbers are defined only as limits... This is why the field of rational numbers, in which such limits may not exist, is too narrow for the needs of mathematics. |
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| p 301 "Interesting limiting processes occur in connection with continued fractions." (see also page 49) | Dienes Blocks explores some previous work I hope to connect up with Dienes or Base 10 Blocks. |
| p 303 (Section 3 Article 1 - second sentence..."We shall now give...function..." | August 15, 2008 - This is currently giving me some trouble - the idea of moving from the limit of a sequence (see p 289)to the limit of a continuous function, - possibly because of misreading the book some years ago, possibly because of the format itself, who knows? - The limit concept seems to have given Newton, Euler, and everyone else trouble, at least as to explanining it, so any simple explanation has a fair chance of being wrong. |
| p 305 ...from the time of Zeno and his paradoxes the intuitive physical or metaphysical concept of continuous motion has eluded all attempts at an exact mathematical formulation. | zeno_1.html |
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p 305 - 306 Only by limiting processes (epsilonDelta) can the fundamental notions of the calculus - derivative and integral - be defined...(the intuitive concept of continuous motion has eluded all attempts at an exact mathematical formulation)...Certainly the intuitive idea of a continuum has a psychological reality in the human mind. But it cannot be called upon to resolve a mathematical impossibility; there must remain a discrpency between the intuitive idea and the mathematical language designed to describe the scientifically relevant features of our intuition in exact logical terms.
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(see also pg 406) November 14, 2008 - There is now an animation, Limit 1; There are a few applets (put links here) what I might want to do is an explanation accompanying the animation... apparently distinguishes continuous motion from logical/mathematical description of motion (using idea of a number continuum?) |
| p 311 - ... all polynomials, rational functions, and trigonometric functions are continuous, except for isolated values of x where the functions may become infinite. | still not very clear how... |
| p 312 Fundamental Theorems of Continuity |
January 22, 2010 The only thing keeping this entry in place is the reference to "nested intervals" (understood as equivalent to Dedikind Cuts and Cantor's idea of Real numbers as 'infinite decimals') - none of which is well understood by me. August 11, 2008 Preliminary animation for Bolzano's Theorem - barely started, to complete will require a closer look at epsilon-delta. Section 5 Article 2, second sentence, "Our objective is to reduce the theorem to fundamental properties of the real number system, in particular to the Dedikind-Cantor postulate concerning nested intervals. (p 68) The second theorem of continuity is Weierstrass' Theorem on Extreme Values. (p313) Another (less fundamental) - Compact Sets (p315) |
| p 314 - ...the graph of a continuous function u = f(x) must have at least one highest and one lowest point" | |
| p 329 - Starting in the seventeenth century, the general theory of extreme values - maxima and minima - has become one of the systematic integrating principles of science | |
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p 342 - As a rule in scientific thinking it is better to consider the individual features of a problem rather than to rely exclusively on general methods, although individual efforts should always be guided by a principle that clarifies the meaning of the special proceedures used. This indeed is the role of the differential calculus in extremum problems. |
I am thinking of "general methods" as referring to computational methods applicable to all, or at least most cases and problems - then this seems to say -calculus provides wide ranging perspective though there may be more accurate means for solutions. (possibly referring to "discrete math" as more accurate?) |
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p 361 - One of the characteristic features of higher mathematics is the important role played by inequalities. The solution of a maximum problem always leads, in principle, to an inequality... ...consider the important inequality between the arithmetical and geometrical means. |
arithmetical and geometrical means interests me because I have already done some animations with them... A short animation sketching out some of the ideas here...more of a placeholder for possible future development. Maxima and Minima. |
| p 362 |
(...positive square root = geometric mean g = sqrt(xy) ) |
| p 366 - The existence of an extremum -
Dirichlet's Principle |
(somewhere online sombody indicated this as of fundamental to Courant's whole approach to mathematics) |
| p369 - Fig 222 (triangle) as illustrative of the difficulties involved in (existence of an extremum problem) | |
| p 370 - ... if there are infinitely many objects in the class, there need be neither a largest nor a smallest number... | |
| p 370 - The mathematical solution of a minumum
problem is not complete until one has provided, explicitly or implicitly a
proof that the set of values associated with the problem contains a
smallest interval. |
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p 381 - ...natural phenomena often follow some pattern of maxima and minima... p 382 - It was observed that stable equilibrium of a mechanical system
is attained if the system is arranged in such a way that its "potential
energy" is a minimum.
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Calculus |
To some extent, all the above was done simply to help me fill in some rather serious gaps in my formal education and general understanding - especially algebra. Any possible use of calculus beyond some minimal parroting of formulas apparently requires some familiarity with those subjects January 22, 2010 I have now done a bit of research and work here - all to the conclusion that a very good understanding of introductory Algebra is prerequisite. For my part, the preliminary sketch for the Fourier animation will serve mostly to sharpen interest in the study of the subject at themathpage.com |
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p 399 - (re: Calculus) There is no longer any reason why this basic instrument of science should not be understood by every educated person. ( Preface v - The goal is genuine comprehansion of mathematics as an organic whole and as a basis for scientific thinking and acting. Understanding of mathematics cannot be transmitted by painless entertainment.) |
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p 400 - Integral - The need for a more general method of computing areas arise when we ask for the area of a figure bounded not by polygons but by curves... (...Archimedes (287-213 B.C.) computed the areas of curvilinear domains as the limit of the areas of a properly chosen sequence of inscribed polygonal domains with an increasing number of sides...a "naive" attitude that curvilinear areas are intuitively given entities to be computed...in the 17th century the areas for a number of other curvilinear geometric entities were computed with special methods for each...since Gauss (1777-1855 A.D.), the idea is that this process is not so much calculating an area, but defining the integral of a function p464) [ror - September 30,2008 - as I understand it today, this makes sense when differentiation is understood and understood as an inverse relation to integration...p 427, 436 ] .
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http://pages.intnet.mu/ p 401 - (calculus replaced such special and restricted proceedures for individual objects by a general and powerful method)
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| p 402 (...the area...expressed by this limiting process...we call by definition the integral...) | . |
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p 404...the word integral was coined to indicate that the whole or integral area A is composed of the "infinitesimal" parts f(x)dx. ...the limit concept (ror - stated elsewhere to be a "process") and nothing else is the true basis for the definition of the integral. |
see also pg 305 (Only by limiting processes can the fundamental notions of the calculus - derivative and integral be defined.) |
| 406 (bottom) Only after much experience with specific cases was a general approach to the problem opf integration found in the systematic methods of sthe calculus...will discuss... "special problems belonging to the "pre-calculus" stage, for nothing can better illustrate integration as a limiting process. |
Courant Calculus 406 - Has been started (November 14, 2008) At the moment it just explains some difficulties I have. In the book, some rather similar trivial functions are used to lead up to the "simplest passage to a limit" in the case of differentiation. (p 418) CourantRobbins at least makes it appear the process can be comprehended by these simpler (trivial) cases - There might be no need to go into a greater amount of complexity. For these reasons I am thinking of using the three functions here in my animation...Nothing is written in stone...there are almost 90 pages on the calculus I would like to study for a bit... December 16, 2008 -The following animations address a number of related issues- they have been updated to link back here: Integration 1, Integration 2 and Integration 3 Based on the mathtutor video noted therein. The video filled in some detail missing or at least difficult for me to understand from Courant Robbins. The mathtutor site seemed what was needed at the time and its stated purpose includes help for those with some deficiencies of math background. As usual, creating these animations helps me to analyize the processes so they can be put in the new format and I really cannot do much math unless it is focused on something immediately practical. |
| p 416 - 2. The Derivative as a Limit |
Preliminary sketch for the idea that the tangent to the curve of a function is the limit (of a sequence of secants.) secant.html Secant - (L. secare - to cut) |
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p 417 f(x) = height of curve above point x |
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p 426 - 2nd derivative rate of change of slope |
animation idea - fade function curve out and just show linear slope line in motion.... inflection?, change of direction of concavity |
| p 433 - "...natural to search for adequate definitions of area and slope as "things in themselves" ...But...to see in limiting processes their only relevant definitions is in line with the mature attitude... | "things in themselves" may be a bit of a leftover ;from Kant or something but "understanding area and slope as process" might be a main focus of an animation...how??? |
| p 436 Fundamental Theorem - ...reference to p 412 (...the value of the integral in no way depends upon the particular name x chosen for the independent variable in f(x) |
preliminary animation Fig 275 p 437... This is not introduced until a thorough study of both integration and differentiation - I was thinking 'if its fundamental, maybe I should learn it first' - but that does not appear to be a good idea - more like - 'learn integration and differentiation first then learn how they work together to create fundamentally good stuff.' _ I'll googlize this a bit more. |
| p 462 ...(vibrations provide an elementary illustration of Newton's method) | |
| p 464 - Instead of considering
the "area under the curve" y = f(x) as a quantity which obviously exists
and can be expressed a posteriori as the limit of a sum, we define the
integral by this limit, and consider the concept of integral as the
primary basis from which the general concept of area is afterward
derived (a posteriori - derived by reasoning from observed facts...) |
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| p 465 - (Sum of a Continuous Function) The sum S(sub n) for a given continuous function f(x) tends to a definite limit A, which is independent of the specific way in which the subintervals and points...are chosen. By definition, this limit is the integral ...the existence of this limit requires analytical proof.. | |
| p 475 (Newton's...discovery...that...) the elementary binomial theorem can be extended from positive integral exponents n to arbitrary positive or negative, rational or irrational exponents a. |
cf William Dunham, "Journey Through Genius " Penguin (1991) Wiley (1990) p165-171 [gets roots of any order] [I am thinking here of the quadrants in Cartesian coordinates - they were not really invented for 2 generations after this but a prior author (Bull?) indicated Newton as "thinking in those terms+-" |
The Continuum Hypothesis mentioned at page 88 of Courant Robbins has to do with the issue of whether a set of numbers exists between the set of integers and the set of real numbers. Apparently it does not, as I had originally thought (by the most logical rendering of the name in standard English) strictly have to do with the existence of a "number continuum" per se which Courant Robbins states is the "...basis of mathematics..." (p72 - 1. The Basic Principle)
The whole issue is rife with logical problems, which seems both illogical to ignore and as unlikely to completely resolve as an equal tempered chord. The issue is treated more currently and by the more knowledgable if not necessarily the more correct in the links below.
1997 - THE CONTINUUM HYPOTHESIS By Nancy McGough
2. http://findarticles.com/p/articles/mi_m1200/is_9_164/ai_108050571
2003 - Hugh Woodin, a mathematician at the University of California, Berkeley, may finally have found a way to resolve the issue, long considered one of the most fundamental in mathematics.
3. Also
http://pass.maths.org.uk%20/issue47/features/elwes2/
Cantor
and Cohen: Infinite investigators part II The continuum hypothesis
4. The following articles discuss the controversy more or less to opposite conclusions in language more or less comprehensible to me:
Lawrence Spector
http://www.themathpage.com/aCalc/real.htmKeith Devlin
http://www.maa.org/devlin/devlin_11_06.html
5. CourantRobbins - In a section on epsilon-delta and "Limit", if I understand correctly, treats the existence of a "number continuum" and the surrounding set theory as something like a useful expedient, not written in stone but to be followed in order to build new, more complex math safely, unless or until it is proven false.
p305 - "Certainly the intuitive idea of a continuum has a psychological reality in the human mind. But it cannot be called upon to resolve a mathematical impossibility; there must remain a discrpency between the intuitive idea and the mathematical language designed to describe the scientifically relevant features of our intuition in exact logical terms."
p xix - "...Fortunately, creative minds forget dogmatic philosophical beliefs whenever adherence to them would impede constructive achievement."
p 88 - As to the apparently misnamed or mistranslated and separate issue of "The Continuum Hypothesis", and the meaning of ""mathematical Existence, "Luckily, the existence of mathematics does not depend on a satisfactory annswer".