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_Why_Slopes_&_More_Math_1995

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  14 Limit of a Fn.  Back ] Home ] Next ]    

Limit of a Function

  • [Play Video]  4½ minutes: Algebraic View of Limits. Example involving sums and quotients.
  • [Play Video]  5½ minutes: Limits and Error Control for Linear Expressions
  • [Play Video]  2¾ minutes: Error Control to N decimal Places, say 5 or 10. 
  • [Play Video]  3¼ minutes:  Limits as Error Control for an unlimited number of decimal places. 

Suppose f(x) is a function of real numbers x and that it is defined on an interval containing the number a. [Limit of a Function]A function f(x) converges to a finite limit at the point x = a if and only if there is a real number L such that for every integer n, there is an m such that
|x-a| < d = 1
2
1
10m
    implies    |f(x)-L| < e = 1
2
1
10n
In the latter case, a limit L is said to exist and we write
L =
lim
x® a 
f(x)
The in-line expression limx® a f(x) and the displayed expression

lim
x® a 
f(x)
should both be read as the limit as x goes to a of f(x). Here remember to read f(x) as f of x.

Continuity of a function f(x) at a number a corresponds to the requirement that the limit L = f(a). But it is possible for the limit L = limx® a f(x) to exist and not equal f(a). See the chapter Slope Approximation.

The rest of this chapter can be read lightly in the first instance. The next sections are not needed in the immediately following chapters.

 

Why Slopes
and
More Math

understanding & explaining
Reason and Math
Volume 3
Printed in Canada
ISBN 0-9697564-3-7

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Content Guide
Foreword
Chapter Descriptions
1. Introduction
Preview -why slopes in 1983
2. Second Preview Begins
2 Skier in Motion (V)
2 The Skier (V)
2. Position Dependent (V)
3 Slope & Extrema (V)
4 Single Factor Analysis (V)
4 Two Factor (V)
4 More Factors (V)
4 With Divisors (V)
5 Maxima & Minima Tests
6 Jumps & Discontinuities
8 Review  (optional)
9 On Calculus Studies
11 Slope of Slope
13  Acceleration
14 Limits & Error Control (V)
14 Limit of a Fn.
14. Limited Error Control
14 Signif. Digits
14 Cauchy Limits
14 Sequence Limits
14 Decimal Arith.
15 What is Slope (V)
15 Slope Calculation (V)
15 Slope, a Limit
15 Tangent Lines
15 Linear Approx.,
15 Limits via Algebra (V)
15 Recap.
PS.Chain Rule for Polys
PS Chain Rule- General  (V) -
PS More Chain Rule (V)
PS - Sign Analysis (V)
16 What is Velocity
17  What is Area
18 Integration
18 Area Calculation
18  Fn DefN, 6 Ways
19 Logs & Powers
19 Natural Log.
19 Exponential Fn.
20 What's Next
21 Add Vectors
22 Complex #'s
23 Complex #'s
23 Trig Identity
23 Proofs of.
24 Complex Logs etc


If  you like Volume 3  you may also like  Three Skills for Algebra , Exponents & Radicals Exactly,  complex numbers, Euclidean Geometry , More Calculus and  Pattern Based Reason  as well. 

Units in Calculations:
7 Velocity
7 Varying Velocity Example
7. Velocity Calculation
7 Changing Units
7 Same Velocity  Motions
10 Slopes without Units.
10 Units & Slopes
10  Units in Cost vs. Quantity
10  How Units  Appear
10 Unit  Elimination
10 Partial Elimination
10 Interest & Units
12 More on Units

Enriched material: The Appendices of Volume 3 are located in the Real  Analysis  Area.

Pigeon Hole Principle
Constant Difference Thm
Continuous Functions
Rational Functions
Mean Value Theorem
One Side Range Theorem
Range On One Side Theorem
Integration & Lipschitz
 Continuity


These appendices continue the
decimal viewpoint of limits, error
control and continuity begun
in Chapter 14. The One Sided
 Range Theorem
is a postscript,
not in printed version.


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