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Online Volumes (Book Orders)
1,  Elements of Reason. 1996
1A. Pattern Based Reason  1995
1B. Math Curriculum Notes 1996
2. Three Skills for Algebra  1995
3.
_Why_Slopes_&_More_Math_1995

More Site Areas 
1.  Solving Linear Equations  2005
2.-Fractions-Rates-Proportns-Units-2006
3.  Algebra, Odds & Ends, HS level-2001
4.-Euclidean-Geometry/Complex No.s 
5.  Analytic Geometry/Functions 2006
6.  Number Theory. 2006-7
7.  Complex Numbers More 2001
8.  Calculus Introduction 2005
More Site Areas 
9   Real  Analysis 1995
10. Secondary IV? maths 2006-7
11. Math Education Essays  2006-7
12. LaTeX2HotEqn: 2004
13. Electric Circuits Etc  2007
14. Quebec Math Education 2004
15-Prequel-to-the-How-TOs-06-2008
How TOs/ Ref.-08- 2008
1. Arithmetic Reference
2. Algebra 
3. More Algebra 
4. Geometry  
5. More Geometry
6. Calculus
7. Logics in Maths

Employ an online or offline tutor at your own risk from 

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CDN :  findatutor.ca 
CDN: .i-tutor.ca
CDN: Montreal Tutors
NZ:   findatutor.co.nz
UK:   tutorhunt.com 
UK:  tutors4me.co.uk
USA:  wiziq.com
USA: ziizoo.com

YOU are better than YOU think. Show yourself  how:

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 For better work & study skills, read logic chapters 1 to 5  in  Three Skills for Algebra. Sooner is better. Good luck.

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 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

Do not leave here without it -  Logic mastery  will develops critical thinking, improve reading and writing, and give a firmer base for work and studies at many levels. Good luck.

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Caution: Site advice is approximately correct, for some circumstances, not all. Site How-TOs are logically developed, but not tried and tested. That leaves room for thought and refinement..

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After logic  (a) continue reading Three Skills for Algebra, chapters 8 to 14  and do so alongside site area on solving linear2007 Equations ; or (b) see this calculus starter lesson and Volume 3, Why Slopes  & More Math, chapters 2 to 6;


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.


Explore collaborative whiteboards from groupboardtwiddla  or scriblink.


Site Lesson Plans

for secondary mathematics and for calculus in secondary schools or college

Innovations in site material in and outside of site books, that advances for mathematics instruction, in providing clearer or alternate ways to learn and teach for comparison, further identify or demonstrate past shortcoming - a benefit of hindsight.

Current State of Site Lesson Plans

  • First, site lesson plans and reforms for secondary I, II and for calculus are well-put with supporting material online in full or almost so.  These lesson plans offer are innovations fresh or recycled likely to ease or avoid difficulties in first time and remedial instruction.
  • Site lessons plans for secondary III is a proposal. Online support may come later through lessons here or links to lessons elsewhere. The study of mathematics can seem endless.  Here is a pause to provide examples and more examples to give a context and hence motivation for fraction and algebra skills and sense, seen or develop earlier,, and to give numerical and algebraic experiences for mentioned or recall in further instruction.
  • Online Lessons and links are online to support secondary IV and V mathematics, say two pre-calculus years of studies in mathematics,  in areas on Euclidean and Analytic Geometry, and on Number Theory. Here the Number theory sections provides more material than needed.  Here the secondary IV lesson plans are online in draft form, 75% done, but still incomplete and subject to re-arrangement. The lean program to be written or identified here will focus on the needs of a first course in calculus.  Just in time instruction is advocated for the sake of leanness and effectiveness in course design.

A theoretical base for senior secondary IV and V mathematics  and calculus, a high school or college subject, follows below with details sufficient for people with a mathematical background to provide what is missing, and thus turn theory into practice.

Secondary I and II lesson plans cover the prerequisites. They develop the fraction and algebraic skills and sense required for senior high school mathematics.

Modern Mathematics Curricula Revisited

The set-based axiomatic, logic-based codification, of  modern mathematics was not designed for classroom, it was adapted to classroom use in the modern mathematics curricula of the 1950's.

While modern mathematics may derives or codifies real numbers and the properties  from say ZF axioms (assumed patterns) about sets, the presentation of the latter belong to advanced mathematics studies that few will meet. In place of modern mathematics curricula and its present day echoes and inconsistencies, after many reforms in the class-room,  a deliberate mixed mathematics approach is recommended.

Modern mathematics course designs of the mid-1950's onward, emphasized the context-free view of real numbers while inconsistently (?) employing the latter in a mixed mathematics manner as coordinates in 1, 2 and 3+ dimensions, and while inconsistently drawing right triangles and taking advantage of similarity properties from Euclidean Geometry, an older view of mathematics, to define trig functions and after that in calculus, to use comparison of geometric areas to evaluate the limit sin(x)/x as a x decreases to 0. At the same time, despite foregoing inconsistencies with lip service to a context free development of mathematics, the modern mathematics curriculum and its echoes, knowingly or not, informally require place or decimal-value representation of real numbers for calculations and coordinates, without sanctioning them. Then calculus further uses decimal arithmetic in the illustration of limits and continuity, while its theory depend on decimal-free assumptions and viewpoints of limits, continuity and convergence which do not sanction and which avoids all mention of decimal arithmetic.  There-in lies an inconsistency or lack of connection between practice and theory in the development of mathematics alone.   Finally, the use of geometric diagrams, models and implications in trig and and in calculus of one, two and three variables, the algebraic treatment of units,   the concepts of space, and figures in them, are all part of mixed or applied mathematics - departures from pure mathematics necessary for the exposition or applications outside of mathematics, and so necessary in the secondary and college development of skills and concepts from arithmetic to advanced calculus.

The foregoing inconsistencies, the dependence on diagrams, depart from the initial pure mathematics vocation of the modern mathematics curricula and present-day echoes and delivers instead, an ad hoc or accidental,  inconsistent,  mixed mathematics view of the discipline. The aversion to decimals in axioms for real numbers and all consequences separated the modern mathematics curricula from the common knowledge of arithmetic and real numbers, without sanctioning nor supporting the latter.  

Modern Mathematics Postponed
A Consistent Mixed Math Curriculum

Secondary IV and V mathematics after the informal consolidation of arithmetic and algebraic or literal reasoning skills, may give a deliberate mixed mathematics view and thought-based codification of the subject with the following practices and axioms (assumed or suggested patterns). 

In this approach, properties of real and complex numbers to be implied by geometric- and decimal-based chains of reason . Then  those properties are codified - formally stated as axioms for real and complex analysis with explicit mention on decimal representation or definition of real numbers. The latter sanctions the use of decimals in calculations and in the calculus-level development of limits, convergence and continuity. 

Students of pure mathematics, a minority, will later also meet the derivation of the same axioms and the decimal representation of real numbers from ZF set theory and  or another base for the current form of modern mathematics.  Here the earlier mixed mathematics approach provides the numerical and algebraic experience and context to appreciate the context-free development of algbera, and real and complex analysis in pure mathematics.

Real Number, Geometric Development

  • Numbers with or without signs as prefixes may be used as coordinates along a line following the implicit or explicit choice of a unit length.
  • Unsigned and then all real numbers may be represented as decimals.
  • Unsigned and then all real numbers may be used as coordinates alone or in ordered pairs and triplets in one, two and three dimensions following the choice of a unit length.
  • 1D vectors along a coordinate line exist, and can be added geometrically in a head-to-tail manner.
  • the coordinate description of the addition of vectors along the real number line (following the choice of a unit length) geometrically  implies methods for adding and subtracting real numbers.
  • The coordinate description of whole number multiples, and then proper and improper positive fractions of vectors (following the choice of a unit length) geometrically  implies rules and methods for  multiplication of a real number (the coordinates) by whole numbers, proper and improper fractions.
  • The negative of a vector (-1 times it) can be defined geometrically.  The coordinate description of the latter, geometrically implies the definition of multiplication of a coordinate or real number, by -1.
  • The ability to changes the  unit length (magnitude and then direction) in the coordinate location of points along a line implies and defines a multiplication of coordinates or real numbers. 
  • The geometric addition of vectors can be described using coordinates following the choice of a unit length.  That was assumed earlier. But the result of this addition of a pair or several vectors in the line  is independent of the choice of unit length. The foregoing implies the distributive laws for real numbers.
  • The head-to-tail addition of vectors in the line is commutative.  The resultant of two vectors has a mid-point. Rotation of 180 degrees about it, and reversal of the ordered of addition (if I remember correctly) implies addition commutes geometrically.  As a consequence, the addition of coordinates (real numbers) is also commutative.
  • The product of pair of unsigned whole numbers and fractions, proper or not, mixed fractions included, may be defined or interpreted as the area of  a rectangle.  Since the area is independent of the order of multiplication of the sides of a rectangle, the product of unsigned coordinates is commutative for coordinates with finite decimal expansions - continuity implies for all unsigned coordinates.  (Optional: If multiplication of real numbers follows the rule, multiply the signs, and multiply the magnitudes or unsigned part, independent, the commutatively of products of real numbers follows from the study of 3 more cases, 4 in all).
  • The product of unsigned numbers is zero when and only when one of the factors is zero. The foregoing "follows" from the decimal method of multiplication and from the area viewpoint of products. 
  • The product of triplet of unsigned whole numbers and fractions, proper or not, mixed fractions included, may be defined or interpreted as the volume of  a box with square corners..  Since the volume  is independent of the order of multiplication of the sides of a rectangle, the product of a triplet of unsigned coordinates is associative for coordinates with finite decimal expansions - continuity implies for all coordinates.
  • The resultant of a head-to-tail addition  of three vectors in the line in sequence implies the sum of the first two vectors with the third equals the sum of the first with the sum of the last two.  Hence head-to-tail addition is associative geometrically. Hence, the addition of coordinates is also associative.
  • Points in the plane can be located using rectangular or polar coordinates. This description is dependent on the choice of a unit length, and the direction of the x-axis. Coordinates may involve degrees in the first instance.
  • Points in the plane can be added using rectangular coordinates. This addition is commutative and associative due to the properties of coordinates, a.k.a. real numbers.

Complex Numbers and Trig, Geometric Development.

For details start with the first site lesson on complex numbers for details - it is outside the complex number site area. Then visit the complex number site area.

  • Points in the plane can be multiplied using polar coordinates via the rule: add the angles, multiple the lengths.  The properties of coordinates (real numbers) implies this multiplication is commutative and associative.
  • The identification of a horizontal axes with a real number line, the introduction of real and imaginary parts (rectangular coordinate viewpoint and a change of notation) implies real numbers can be multiplied using the rule: add the angles and multiple the lengths. That rule is consistent with the earlier rules for multiplying real numbers. It could obviate the need for an earlier definition of multiplication for signed numbers.
  • The distributive law for complex numbers is a consequence of a change of unit length. (Rectangular and polar coordinates are dependent on the choice of a unit length and orientation in the plane. The assumption that the head-to-tail addition of vectors in the plane is independent of an selected coordinate system -  in other words,  independent of the length and direction of the "horizontal" unit vector, for the latter determines the "vertical" unit vector - implies multiplication of complex numbers distributes over addition.)
  • With the aid of rectangular and polar coordinates, (periodic) trig functions can be defined for all (real) angles - obtuse or acute included - with the aid of a unit circle. Similarity of right triangles implies (?) this unit circle definition is independent of choice of unit length. Similarity of right triangles also implies that trig functions for acute angles may be calculated using the ratios of sides in a right triangle. Courses have the option of introducing trig functions with the unit circle before introducing right-triangle based or related trig calculations. The properties of trig functions are easy consequences of the field properties of complex numbers. The latter can be from geometry and properties of real numbers (decimal arithmetic).

Calculus

Cognitive Dissonance: In my earlier and literal adherence to modern mathematics curricula, the use of diagrams and decimal calculations, and other hand-waving devices not sanctioned by the axioms in the modern mathematics curricula was a source of discomfort - a departure from the rigorous development ideas and concepts which I was suppose to support or encourage.  The discomfort began in trigonometry with the use of right triangles and ratios of sides to say how to compute and thus define trig functions.

Calculus is the subject which requires algebraic ways of writing and reasoning, and arithmetic skills and sense at full strength.  Calculus courses tend to use diagrams and decimals to develop or illustrate concepts along side the statement of theorems and rules which may or may not be proven. Here adherence to pure mathematics and the decimal-free viewpoint of real numbers makes the exposition harder to follow - brings about more algebraic shocks than need-be. Exposition demands some hand-waving, some departures from pure mathematics.  The diagram-free pure mathematics representation and definition of trig function is not for begginners. That the exposition or introduction of trigonometry and calculus requires a mixed mathematics approach. The latter can be presented or developed in a thought-based or logical fashion in a manner, self-contained, sufficient for the needs of other disciplines, and sufficient for the development of the algebraic-deductive and computational ability prerequisite to the study by a few of modern mathematics.

Modern Mathematics Postponed
A Consistent Mixed Math Curriculum

In the foregoing development, properties of real and complex numbers are geometrically implied.  Elements of this mixed mathematics development can be seen in the geometric or vectorial illustrations of properties of real numbers when they are introduced earlier in high school or primary school, at least where real numbers and there properties are  not learnt fully by rote.

Once the properties of real and complex numbers have been geometrically implied, and once the decimal representation of coordinates, that is real numbers, assumed, a reformed or modified modern mathematics program, echo of the late 1950's, can be begin again with the set-based statement of the axioms - here arithmetic patterns algebraically described  for both real and complex numbers - plus explicit assumptions about the decimal representation of real numbers.  The latter provide continuity with the common knowledge of arithmetic with decimals, alone or in the numerators and denominators of fractions. The latter provides a mixed mathematics framework for the further development of trigonometry and calculus.

Then limits, continuity and convergence in elementary or advance calculus explicitly exploit the decimal representation of real numbers.   Courses on analysis, real or complex, may switch to decimal free viewpoint and even included the context, coordinate-free, development or derivation  of real and complex numbers, and then functions of real and complex variables, from ZF decimal-free assumptions about sets.  See site volumes 2 and 3, and site areas on number theory and complex numbers to learn more.

The foregoing program I suspect is generally solid. Most, if not all, elements are online. That being, the program is understood when and only when readers see possibilities for improvement.

Remark 1, Why Sets: Before pure mathematics courses on real and complex analysis, set formality in the development and description of of real numbers and complex numbers and functions provides a precise framework for this development, for counting methods in combinatorics  and probability. So set-based language and properties of sets can be woven into a mixed mathematics curriculum without harm and with some benefit.

Remark 2, abrupt introduction of a concept: Between the presentation of functions as calculation, mapping or assignment rules, and the identification of functions with their graphs, there should not be an abrupt transition.   The identification of functions with their graphs, a set of ordered pairs which satisfies a vertical line property,  is a feature of modern mathematics.  We might avoid the transition altogether by identifying the graph of a function with a set of ordered pairs, and explaining how a set satisfying the the vertical line test yields a function (a computation or assignment rule) via a vertical line based calculation or assignment method. In secondary and college level mathematics, I would recommend talking about functions as rules and not identify functions with their graphs, even though there is a one to one correspondence between functions and sets of ordered pairs which pass the vertical line test.  The identification is a technical complication but left for later, a  technicality introduced the thoughts of progress in education extended to the inclusion of more and more college level material in high school courses. See the site area on analytic geometry coverage of functions for an effort to avoid the abrupt transition.

Remark 3, the problem of units: In applications, in the physical sciences and in economics, quantities of length, time, mass and money appear alone or in ratios.  Axioms for calculations for quantities need to be devised to sanction the calculation, numerical or algebraic, that involve units and changes of scale in units. While students may first obtain a pre-axiomatic, thought-based knowledge of mathematics through calculation practices with and without units that yield repeatable, reproducible and hence verifiable results, the statement and use of axioms for real and/or complex numbers without mention of units may be sufficient to introduce the logical organization and codification of pure mathematics, but is insufficient for the requirement of applied in the domain of numerical and algebraic calculations with units. While quantities and operations on them can be mapped into numbers and operations on them, and so into the domain of pure mathematics,  via an explicit choice of a system of units which eliminates or factors the units, axioms for real and complex quantities would be useful if stated explicit or verbally described and sanctioned along side the statement of axioms for real and complex numbers. 

Remark 4, solution (?) for the problem of units: The associate law for addition and multiplication of three real or complex numbers can be stated algebraically. However in practice, the sum and products of terms can be computed in many ways. While advance mathematics can inductively define and thus formally describe and imply  how the order of addition and multiplication in sums and products of terms and factors does not affect their values, in early classes we may state the associative law or axiom for sums and products of three terms or factors, and then verbally imply the more general law or consequence.  A similar approach may extend axioms for real and complex numbers to real and complex quantities, and so permit units to be carried through calculations.  Axioms for real and complex numbers sufficient for the codification or formalization of pure mathematics then represent a partial codification or formalization of mixed mathematics.

Remark 5. In modern mathematics, the context-free development of real numbers from axioms (assumed) patterns involving sets is not for novices. The connection of context-free modern mathematics to the concrete and hands-on use of coordinates in diagrams or physical diagrams requires or implies mixed mathematics assumptions about geometry with or without coordinates, assumptions that may have predated the context-free development of mathematics. Since those assumptions or equivalent ones have to made in secondary school mathematics, the mixed mathematics program above exploits such assumptions or equivalent one to geometrically or physically imply the properties of real numbers 

 

 

 

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