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A Calculus, Preparation for Calculus and Math Ed ReformWebsite, Etc.

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1,  Elements of Reason.
1A. Pattern Based Reason 
1B. Math Curriculum Notes
2. Three Skills for Algebra
3. Why Slopes & More Math
(a calculus preview/review)

Mathematics Course Designers: LAMP offers food for thought.
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2. Solving Linear Equations
3. Fractions Ratios Rates Proportions & Units
4. Euclidean Geometry
5. Analytic Geometry/Functions 
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7. More Calculus
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||Définition d'une variable || Algèbre || Arithmetique || Logique ||La raison basée sur les règles et modelés||
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YOU are better than YOU think. Show yourself  how:  

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Read  logic chapters 1 to 5  in online volume Three Skills for Algebra  for greater skills & confidence in  work 
and study

Learn to read notes and textbooks like a lawyer, so that no nuance, no subtlety and no clause escapes your 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

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;

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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.

Domains of Functions

The domain of a function is the set of values for which it is defined.  Sometimes it is easier to say where the function is not defined.  

We assume our functions are real valued.  

So values of the independent variable which would involve the square root of negative numbers and hence complex numbers for values are not allowed.  Follow that convention until you are in course or a topic involving complex-valued functions.

Domains of Basic Functions 

  • Polynomials p(u) are defined for all real numbers
  • Rational functions (the ratio p(u)/g(u)  of two polynomials) are defined at points where division by zero appears, that is where g(u) = 0. 
  • sin(u) and cos(u) are define for all real numbers u. . 
  • The ratios and reciprocals of the sin(u) and cos(u) are defined except those points where denominators would  equal zero.
  • logarithms are defined only for non-negative real numbers - when functions are restricted to being real-valued.
  • square roots and even roots are defined only for non-negative real numbers - when functions are restricted to being real-valued.
  • odd roots are defined for all real numbers.
  • Powers xq where q = m/n and m = 2k is even and n odd is define for all real numbers.  Here  xq =  (xm)1/n =  (x1/n)m . Moreover,    xq = sign(x)   |x|q 
  • Powers xq where q = m/n and m is odd  even and n even is define for all non-negative numbers. Here  xq =  (xm)1/n =  (x1/n)m   But  both   (xm)1/n and  (x1/n)requires the computation of an even root of a negative number when x is negative and n is even. So is not possible for real numbers when functions are not allowed to be complex-valued.
  • When q = m/n and a > 0,  aq = exp( q ln(a)). 
  • When q = m/n and n is odd, and x is non-zero,   |x|q = exp( q ln(|x|))   (Why?) and  xq = sign(x)|x|q = sign(x)*exp(q*ln(|x|))   

Composition of these basic functions yield further functions.  The domain of the resulting composite function depends on the domains of the composed functions.  Basic and composite functions may then appear in sums, differences, products and quotients to provide further further functions.  Reciprocals and Quotients of functions, basic or composite or more complicated,  introduces points where the further function is not defined in order to avoid division by zerio.

Remark: A finer discussion of the connections between powers, logarithms and exponentials is possible.  In a second course on calculus, one can show that that the properties of natural logarithms and exponential function  imply  f(x) = exp(x ln(a)) is a continuous function with the property that f(q) = aq  when a > 0 and q is a rational number, positive, negative or zero. So we define ax = exp(x ln(a)) for all real numbers x. 

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More Calculus
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Calculus Videos
0.   First Calculus Preview
0. Triangle Inequality
0 Inequalities
0. Solving Inequalities
1. Distance+Midpt Formulas
1. Function Domains
1.Polynomial Domain+Range
1. Fn:  Linear Combinations
1. Fn Composition II
1. Fn Composition I
1. Solving y**n = x**m
2 .Real Numbers
2. Limits Numerical View
2. Limits,. Formal Definition
2. Limit Properties Numerically
2. Decimal View of Limits
2. Error Control View
2. Limits & Continuity
2. Limit Vals via Substitution
2. Limits & Composite Fns
2.. Limit Examples
2. One Sided Limits
2. Infinity and Limits
2. Parameters in Limits
3. Derivative Motivation
3.  Derivative Definition I
3. Derivatives Definition II
3. Calculus: Why Radians
3 d/dx of sin(x) & cos(x)  (I)
3 d/dx of sin(x) & cos(x) (II)
3.Sum Rule
3. Product Rule
3. Power Rule
3. Previous Rules Combined
3. d/dx for Polynomials
3. Reciprocal Rule
3. Reciprocal Law: sec & csc
3. Reciprocals & Power Rule
3. Power Law for Integers < 0
3. Quotient Rule
3. Quotient Rule Examples
3. Quotient Rule: tan & cot
3.  Linear Chain Rule
3. Chain Rule for Powers
3. Chain Rule - Polynomials
3. Chain Rule Examples I
3. Chain Rule Examples II
3. Linear Approximation I
3. General Chain Rule
3. Inverse Fns Derivatives
3. Chain Rule: ln(x) & exp(x)
3. Square & Cube Roots
4.  Linear Approximation
4. Second Derivative Test
4. Sketch y = x^3 - 6x^2- 12x
4. Sketch y = x^3 - 3 x^2 - 9x
4. Sketch y = 1 - 1/(1+x^2)
5. Indefinite Integrals A
5. Indefinite Integrals B.
5  Indefinite Integrals C
6. Definite Integral D
6. Area Under Curves
7. Volume of a Sphere

To Learn More, visit Volumes 2 and 3.


Advanced Topics

Limit Properties Algebraically
Pigeon Hole Principle
Bolzano
Constant Difference Thm
Continuous Functions
Rational Functions
Mean Value Theorem
One Side Range Theorem
Range On One Side
From Lipschitz Continuity

To Learn More: Visit Real Analysis.

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