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Summary: While rational powers and roots may be defined as solutions of
equations, solutions to be found, the can be calculated with
formulas involving logarithms and inverse logarithms (exponential)
functions. Those formula allow irrational powers or exponents to be
calculated - saying how to calculate a number or quantity defines
it. Formulas for compound growth and decay, for compound interest,
for radioactive and so on can be used forwards and backwards. The backward
use involves logarithms. Powers and roots are appear in the
following calculations: Compound growth and decay models: compound interest,
population growth, radioactive decay. Solution of equations involving polynomials.
Exponents and Radicals - New Version
1: Logarithms
and Exponentials Only - Cryptic Theory ; The natural logarithm and its inverse
(the exponential function) may be calculated with the aid of tables of
values or with the aid of calculators. Here is a short form of the next
page.
2: Logarithms,
Exponentials, Powers and Radicals - Long Theory This
page shows how to calculate powers and radicals in terms of logarithms and
exponentials.
Showing how to
calculate powers and radicals with the aid of the natural
logarithm and exponential function makes the domain of definition of
powers and radical clear and obvious. That simplifies the treatment of
exponents and radicals at the expense of assuming the properties of natural
logarithm and the exponential function. The precise development may clarify
or replace high school developments.
3: Solving
A = P(1+i)n for n.
4:
From exponential function expression for rational powers of real
numbers to exponential function expression for real powers
5: Calculator Viewpoint: Calculator
exercises provide work to do alone or in groups to provide an
calculator based operational command of roots and powers, logarithms and
exponentials, etc. These exercises are optional. They could also stand
alone to provide a calculator based viewpoint. Given first, they could provide
a base for the earlier lessons.
6: Growth and Decay Models in Biology
- A dozen exercises.
The exercises here explore compound population growth &
decay and population doubling and/or half-time modes
half-life and the relationships between them.
7: (To Come) Forward and backward use of compound growth models
half-life, doubling time and exponential form.
Reference:
(1) Chapter
14 in Volume 2, Three Skills for Algebra, introduces the
forward and backward use of the compound interest formula A =
P(1+i) n., and calls the forward and backward use of
formulas, a 4th unifying skill and theme for algebra. The backward use in
Chapter gives formulas to use to for interest rate i and the power n for
two separate cases where each number is the only unknown in the formula.
The derivation of those formulas could be an application of the algebraic theory
in this section. Reading chapter 14 before the study of this area would
provide motivation for it and introduce the unifying phrase and
theme "forward and backward use of formulas" for the development of
algebraic skills. Reading it after steps II and IV above provide a fuller
understanding of that theme - The theme has been present in high school and
college mathematics and science course, but it has been vocalized. That
vocalized or verbalization in the issuance of the phrase represents an advance
for mathematics education.
(2) Chapters
19 in Why Slopes and More Math, presents the area under
a curve development of the natural logarithm, and employs that as a
starting point for the definition of all logarithms, the development of
the fundamental theorem of logarithms, and the introduction of
exponential functions. There-in lies a justification of the properties
of logarithms and exponential function given without proof in the above
treatment of exponents and powers. The justification would be
optional spare-time reading for students of calculus or gifted
precalculus students. The term spare-time is important. This optional
reading should not distract for in school performance and duties of any
student. Marks count.
Links:
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Logarithms, Exponents, Powers and Radicals
>> How to compute and carefully define in
terms of exponential and natural log functions <<
Section Entrance 1. Short Theory 2. A More Complete Theory 3. An Application 4. More on Rational & Real Exponents 5. Calculator Exercises 6. Population Models Exercises Algebraic Summary Postscript
Old Version: All in one page:
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For
Senior
High School & Calculus Students
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Words to clearly
introduce algebra and variables
have been missing in course design. For people who cannot do
algebra,
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the missing words may
explain or ease their difficulties. Volume 2 ,Three
Skills for Algebra, in Chapters
8 to 14 & 18 etc, puts words before symbols to
providing the missing words in a way that enrich the
comprehension of all. Those words form the middle part of a algebra
(and logic) lessons aimed at helping or improving all
of high school mathematics and also calculus course
design & delivery.
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For Avid Readers in School & Out -
Online Books
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
Tour their forewords.
Calculus Prep or Help: See Volumes 2 & 3,
and this bigger
Calculus
Guide. If your
calculus questions is not answered here, submit
it. Over time, that may complete the site development of
calculus.
For Parents: Speaking
Skills, Reading
& Writing,
Preparing for Science, ends,
values and methods for work and study, parent- friendly maths
skill development booklets for ages 4-14.
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Mostly
For High
School
Intro to Solving
Linear Equations
- a different paths for junior and even senior high
school students. Question for Tutors: When do
you use and when you skip the stick diagram method
here?
Fraction
Skills, thought-based development, Ages 10 to 14 may need a
tutor. Students who have to understand in order
to do may like the development in all or part.
For Senior
High School Mathematics & Calculus
5
wordy Logic
Chapters
4 curious Algebra
Chapters
Words before & besides symbols. A Key Algebra
forward & backwards Chapter
First Calculus
Preview (1st intro)
Four Calculus
Chapters
(2nd intro)
Intro to Complex
Numbers (long)
Intro to Mathematical
Induction (romantic & wordy at first)
Tutors & Instructors:
These lessons introduce skills differently Would you
recommend them?
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More Topics
1. Decimal
Arithmetic Reference!
2. Integers
- Intro to Signed No.s
3. Fractions
- fully explained.
4. Fractions
with Units
5. Number
Theory,
6. Solving
Linear Equations
7 Formulas
for- & backwards -
8. Proportionality,
Back- & For-wards.
9. Logic
Chapters:
10. Euclidean-Geometry
11. Slopes
& Equations of Straight Lines. (Take
I. See take II below)
12. Why
Study Slopes.
13. Maps,
Plans, Similarity & Trig,
(Take II included here)
14. Quadratics:
Starter lessons
15. Polynomials:
Starter lessons
16 Why
Factor Polynomials:
17 Functions
- Forwards & Backwards.
18. Exponents,
Radicals & logs.
19. Complex
Numbers before trig (new advance/ starter lesson)
20. DC
Electric
Circuits Etc
21. Real
Analysis
22. The
Olde Complex No, Trig
& Vector Section.
23. More
Calculus Stuff
- written after Volumes 2 and 3.
Level I Material: New Stuff
Time and Date Matters
Level I Arithmetic.
Money Matters
Measurement Matters
Matters of Chance (Risk Control)
Logic
Chapters
(leave what's not clear in Level I to Level II)
Using/Making Maps and Plans.
(A variant of
Maps,
Plans, Similarity & Trig, to
appear here).
For Instructors
-
Education
Essays
(opinions,
possibilities, references)
- Free
Advice and Directions for teaching primary & high school maths
will be given in online meeting place with voice &
whiteboard.
- Math & Logic How-TOs
1. Arithmetic
2. Algebra
3. More Algebra
4. Beginner Geometry
5. More Geometry
6. Calculus
7. Show Work or Logic
These may be too dense for students. Offering ideas to change
education makes this site different. Nothing
ventured, nothing gained. Site material is
mathematically correct, and where not, please report
errors. The two level program POMME in the site
entrance implies multiple paths for instruction. Supporting
those paths in turn implies a clear destination for
site development and perhaps a new name.
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