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Have your gifted students read logic
chapters 1 to 5 in online volume Three
Skills for Algebra for greater skills & confidence
in work
and study.
tell students to read notes and textbooks like a lawyer, so that no nuance, no
subtlety and no clause escapes their attention. |
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Logic
chapters 1 to 5 re- appear not in sequence, as is or longer,
in Volume 1A, Pattern Based
Reason, Bon Appetite.
Logic
Mastery
Amazing, Amusing, Amorous, Delicious, Delightful, Edifying,
Strengthening Elixir.
It eases work & learning difficulties Makes the hard easier. Opens eyes.
Leads to greater precision.
in reading and
writing
Tell students that Logic
mastery makes the hard, easier. Logic
mastery leads to better, stronger and richer comprehension. Logic
mastery improves reading and writing. Logic
mastery ease learning difficulties. Logic
mastery gives a headstart. In sum, logic
mastery will develops critical thinking, improve reading and writing,
and give a firmer base for work and studies at many levels. Good luck.
After logic,
(a) continue reading Three
Skills for Algebra, chapters 8 to 14 and do so alongside site area on solving
liinear Equations ; or (b) see this calculus
starter lesson and Volume 3, Why
Slopes & More Math, chapters 2 to 6. In Volume 2, Three
Skills for Algebra, a 4th skill for algebra appears in Chapter 14. It
provides a unifying theme for high school mathematics - equations and formulas
may be used forwards and backwards, directly and indirectly, numerically in arithmetic
solutions & with literals in algebraic solutions.
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Caution: Site advice is approximately
correct, for some circumstances, not all. That leaves room for thought |
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What may be learnt and when depends on how skills
and concepts are developed. Making the hard easier and clearer will allow
earlier & richer development of skills and concepts.
Try the Twiddla
Whiteboard. In principle, it allows
to people to draw and chat together online on a copy of this webpage or a clean
sheet. The chat may be via text or audio. Visit www.twiddla.com
to set up whiteboards to work with the webpage of your choice.
For online automated help in senior high school maths & calculus,
visit quickmath.com For Automatic
Calculus and Algebra Help with derivatives, integrals, graphs, linear equations,
matrix algebra, visit calc101.com
With overlap, each site quickmath
& calc101offers a different range of
services, some free, some not, all based on webmathematica. Good luck.
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Chapter 9
The Two Ends
Secondary or intermediate mathematics instruction should provide a smooth
transition or bridge between the start and finish of this instruction. For most
who attend colleges, the start is met in elementary or primary school and
represented and the finish is met in college service courses.
College Service Courses
College service courses refer to those courses taught to students not
specializing in mathematics, usually the majority of students in a college.
Calculus, often the lowest level of mathematics taught for credit in a college
exposes students to algebraic thought at its full strength. Miscomprehension of
the algebraic way of writing and thinking usually leads to failure or
intellectual hardship if not in a first, then in a subsequent calculus course.
Calculus instructors would be most content if their students had previously
mastered logical reasoning and the symbolic or algebraic ways of writing and
thinking along with some trigonometry and optionally geometry before entering
calculus [1]. College faculties today in their exposition
of mathematics start almost from scratch [2].
College level instruction in math, commerce, engineering, science and
technology may assume or build on a knowledge of logic, of basic trigonometry,
and of the symbolic and algebraic way of writing and thinking. These skills are
required not only for the exposition and mastery of calculus but also for
computational methods in various disciplines and more advanced mathematics
courses (analysis, abstract algebra, differential equations, numerical methods,
differential geometry).
In college math courses presently taught in North America, there is presently
little emphasis on set theory or derivation of mathematics from first
principles. Algebraic and computational skills are emphasized and graded
instead. Science, engineering and commerce departments want mathematics courses
to prepare their students for computation and not the set theoretic codification
of modern mathematics.
Only students specializing in mathematical disciplines [3]
require or employ the set notions of membership, unions, intersections, ordered
pairs and complements. But for students in disciplines not concerned with the
set theoretic codification, wrapping concepts in set theoretic terms may be a
distraction. The wrapping should only employed when it clarifies the exposition,
or provides a second perspective.
Elementary Courses
Primary or early secondary school instruction has say the role of providing a
knowledge of decimal arithmetic, counting and the use of simple formulas. This
instruction leads to a mastery of some rule and pattern reasoning or figuring
and a familiarity with repeatable, reproducible processes and thus their
verifiable results. This rule and pattern reasoning appears before the use of
implication rules that also establish conclusions in a repeatable, reproducible
and thus verifiable manner.
The demands on primary instruction are described next. Note the innovation,
the discussion of rectangular and polar coordinates, and then associated
discussion of navigation and complex numbers. More comments or details will be
given later.
1. Counting, weights and measures.
2. The conversion units of measurement.
3. Formulas for perimeters, areas, volumes and interest (simple or compound)
along with illustrations. These formulas show how shorthand notation
describes calculations that may or might be done or postponed.
4. Decimal positional notation for whole numbers and then denominators and
numerators of fractions. Arithmetic computations should be done by hand and
explained in such a way that students understand or see from examples, their
meaning and justification. The explanation of powers of 10 and perhaps
scientific notation for numbers is part of the comprehension of decimal
positional notation.
5. Repeating and non-repeating decimal expansions for fractions (rational
numbers) and for irrational numbers such as Ö2 and p..
The presumed convergence of these decimal expansions. The physical notion that
each decimal place serves to better locate a point on the real number scale. The
presumed correspondence with numbers and a coordinate axes is exploited here.
6. The need for care in arithmetic and the objective nature of arithmetic.
Arithmetic in primary school should make students aware that a single false step
in a calculation cast doubts on the results of all the following steps.
Arithmetic in primary school should also lead to the expectation of objectivity.
Results obtained exactly should be independent of the computer, here a student
with a pencil and some paper.
7. Round-off problems in calculations, inaccuracy in measurements, and the
number of significant digits in decimal expansion. There should be an
uncertainty of at most half a unit in the last retained decimal place, if the
accuracy range is not otherwise indicated.
8. Measurement of regular and irregular areas by covering them with
triangles, squares or rectangles, and then summing. This approximation of
area, sometimes exact, represents a practical skill. When a region is covered by
small squares, the convergence of inner and outer approximations as the squares
are made smaller could be illustrated. (The outer approximation is the sum of
the areas of squares in the covering which intersect the region. The inner
approximation is the sum of the areas of the squares in the covering which are
included fully in the region.) The approximation discussed here is also a
foretaste of approximation, convergence and summation in mathematics after
arithmetic – an example which can be later recalled in the explanation of
integral calculus, so that the later explanation of mathematics coheres with and
is not disjoint from the earlier description.
9. Coordinates on the line. Students only familiar with unsigned decimal
numbers can be introduced to signed numbers as a means to signal a position on
one side or another of the origin of a line. The height of water above
and below a zero-level mark provides a first example. Temperature measurement in
Fahrenheit and Celsius provide two further examples and show again that the
choice of the origin may be arbitrary. Moreover, addition and subtraction of
positive numbers can be identified with displacements in the positive or
negative direction respectively. Similarly, addition and subtraction of negative
numbers can be identified with displacements in the negative or positive
direction.
10. Cartesian and Polar Coordinates, their use in locating points and
their measurement on maps. Here elements of navigation could be introduced.
Students could be given a map, a starting location for a boat or airplane, and
then asked to track the location of the latter through a sequence of
displacements. The latter could be described with numbers by coordinates shifts
or angles and lengths. They can also be described by arrows or vectors drawn on
a map to represent a sequence of motions. This leads to the (map) addition of
arrows or vectors. Beyond this, the multiplication of arrows or points in the
plane can be easily defined using the add the angles, multiply the lengths
rule for complex numbers. The latter in a pre-algebraic fashion will justify the
law of signs and allow square roots of negative numbers to be identified. Ease
of exposition and visualization is the justification for this last innovation.
It demystifies negative and complex numbers even before algebra is studied.
At the end of primary school, or at the start of secondary school, students
could be shown the mechanics of buying and selling. They could play games which
in the simplest case involve transactions between a customer and retailer, and
in the more complicated case between retailer and wholesaler, and wholesaler and
suppler. Keeping track of the discounts, accounts and methods of payments would
be an exercise in a flexible rule-based reasoning process. Here students could
be challenged and required to do arithmetic without a calculator — tell them
to imagine a power failure. Questions of how to verify results could be done.
Those students required to master the most complicated computations and
transactions would be favoured or better prepared than students shown only the
simplest material[4]. Mastery of decimal arithmetic first
became popular with merchants as a means of doing and recording transactions and
balances. This provides another setting for the discussion or introduction of
positive and negative numbers or balances. The above topics and others are
discussed in the chapter Elementary
Instruction.

[1] The introductory chapters in the companion book Why
Slopes and More Math however assumes a fragile command of the algebraic way
of writing and reasoning, and tries to reinforce it. Instruction in calculus can
be regarded as another or last opportunity to demonstrate and explain the
algebraic thought process.
[2] Many colleges have remedial programs for arithmetic
and algebra skills alongside more advanced, but none the less secondary school
level, pre-calculus courses in algebra or trigonometry.
[3] For instance: probability and statistics,
mathematics itself, electrical engineering, theoretical physics computer
programming or database organization, ... .
[4] In retrospect, the chapter should be callled Symbolically
or Algebraically Described Rules for Arithmetic.
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www.whyslopes.com
Volume 1B, Mathematics Curriculum Notes,
Foreword + Chapters 1 to 10 + 12
Book Entrance Inductive Principles 1 Introduction 2 For & Against Math 3 Algebraic Thought 4 Why Slopes & SQRT of -1 5 Books & Articles to Read 6 Unruly Origins of Algebra 6. Axiomatic Civilization 7 Geometry, 2 Ways 8 Modern Instruction 9 The Two Ends 10 The Transition 10 Explaining Logic 10 Explaining Algebra 10 Why Sets in Math. 12 Four Phases Links
Chapter 11: Primary School Mathematics
11 Primary Math 11 Cue Cards 11 Counting 11 Decimals - Addition 11 Decimals -Times 11 Decimals & Subtraction 11 Fractions and Division 11 Notational Conflict 11 Reciprocals Etc 11 Decimals - Ratios 11 Size Comparison 11 Numbers, +ve or -ve 11 Rename < Sign 11 Complex Numbers
Will provide an alternative to Chapter 11 later, most likely in the Parent's
Area: Help Your Child or Teen
Learn
Most students in high school are not heading for calculus,
but most topics in high school mathematics are present due to calculus.
Preparation for calculus demands their coverage at full strength.
See too, this site 55+, Math
Education Essays. Site areas and pages provide pieces of the a Mathematics
Education, Jigsaw Puzzle, in formation.
-Inductive
principles for course design & delivery require a clear
description of where and how skills and concepts may rest on earlier ones, so
that difficulties may be explained and remedied by looking for what was
missed or forgotten in earlier studies.
Mathematics is a demanding subject. All errors in notation
and comprehension need to be identified and corrected. In
reading, spelling and writing, students have to learn all the letters in the
alphabet, not just some. and memorize spelling. Anything less implies
difficulty.
Likewise in mathematics, students have to master key skills
and concepts, one at a time and one after another. Anything less implies
difficulty.
Modern mathematics curricula introduced an inconsistency
into course design and delivery. They did not sanction the use of decimals nor
the use of diagrams in skill and concept development but decimal arithmetic
and diagrams are needed for student comprehension and for an operational
mastery of quantitative skills. That implies the need for an mixed-math
curricula based on a systematic development of operational skills, sufficient
for applications and sufficient to provide a base & context
for the very optional study of pure mathematis.
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