home *** CD-ROM | disk | FTP | other *** search
- TAYLOR SERIES
-
- This slide show consists of graphs of various functions together with some of
- their Taylor polynomials about the origin.
-
- When viewing the slides, the following keys are operational:
-
- HOME takes you to the first slide in the sequence you selected
- END takes you to the last slide in the sequence you selected
- UP ARROW takes you to the previous slide in the sequence you selected
- F9 immediately quit the program
-
- These keys do NOT operate like that while you are reading this document.
-
- A. exp(x)
- This graphs exp(x) in the interval -2 < x < 2, and then overlays it with
- the polynomials
- 1
- 1 + x
- 1 + x + x^2/2!
- 1 + x + x^2/2! + x^3/3!
- 1 + x + x^2/2! + x^3/3! + x^4/4!
- 1 + x + x^2/2! + x^3/3! + x^4/4! + x^5/5!
- The radius of convergence of the Taylor series is infinity.
-
- B. sin(x)
- This graphs sine(x) in the interval 0 < x < 2π, and then overlays it with
- the polynomials
- x
- x - x^3/3!
- x - x^3/3! + x^5/5!
- x - x^3/3! + x^5/5! - x^7/7!
- x - x^3/3! + x^5/5! - x^7/7! + x^9/9!
- x - x^3/3! + x^5/5! - x^7/7! + x^9/9! - x^11/11!
- The radius of convergence of the Taylor series is infinity.
-
- C. cos(x)
- This graphs cosine(x) in the interval 0 < x < 2π, and then overlays it with
- the polynomials
- 1
- 1 - x^2/2!
- 1 - x^2/2! + x^4/4!
- 1 - x^2/2! + x^4/4! - x^6/6!
- 1 - x^2/2! + x^4/4! - x^6/6! + x^8/8!
- 1 - x^2/2! + x^4/4! - x^6/6! + x^8/8! - x^10/10!
- The radius of convergence of the Taylor series is infinity.
-
- D. 1/(1 - x), -1 < x < 1
- This graphs 1/(1 - x) in the interval -1 < x < 1, and then overlays it with
- the polynomials
- 1
- 1 + x
- 1 + x + x^2
- 1 + x + x^2 + x^3
- 1 + x + x^2 + x^3 + x^4
- 1 + x + x^2 + x^3 + x^4 + x^5
- The radius of convergence of the Taylor series is 1. Notice what is happening
- near -1. The larger the polynomial, the better it is at approximating the
- function.
-
- E. 1/(1 - x), -2 < x < 2
- This graphs 1/(1 - x) in the interval -2 < x < 2, and then overlays it with
- the polynomials
- 1
- 1 + x
- 1 + x + x^2
- 1 + x + x^2 + x^3
- 1 + x + x^2 + x^3 + x^4
- 1 + x + x^2 + x^3 + x^4 + x^5
- The radius of convergence of the Taylor series is 1, but the function 1/(1-x) is
- defined for all x except 1. This is a good way of graphically demonstrating
- that a function may a have a Taylor expansion valid in a smaller domain than the
- function is defined. The interval of convergence is shown on the screen and it
- is easy to see that for x < -1 and x > 1, the approximation becomes worse as the
- number of terms increases, as distinct from what happens for -1 < x < 1.
-
- F. arc tan(x), -1 < x < 1
- This graphs arc tan(x) in the interval -1 < x < 1, and then overlays it
- with the polynomials
- x
- x - x^3/3
- x - x^3/3 + x^5/5
- x - x^3/3 + x^5/5 - x^7/7
- x - x^3/3 + x^5/5 - x^7/7 + x^9/9
- x - x^3/3 + x^5/5 - x^7/7 + x^9/9 - x^11/11
- The radius of convergence of the Taylor series is 1.
-
- G. arc tan(x), -2 < x < 2
- This graphs arc tan(x) in the interval -2 < x < 2, and then overlays it
- with the polynomials
- x
- x - x^3/3
- x - x^3/3 + x^5/5
- x - x^3/3 + x^5/5 - x^7/7
- x - x^3/3 + x^5/5 - x^7/7 + x^9/9
- x - x^3/3 + x^5/5 - x^7/7 + x^9/9 - x^11/11
- The radius of convergence of the Taylor series is 1, but the function arc tan(x)
- is defined for all x. This is a good way of graphically demonstrating that a
- function may a have a Taylor expansion valid in a smaller domain than the
- function is defined. The interval of convergence is shown on the screen and it
- is easy to see that for x outside this interval the approximation becomes worse
- as the number of terms increases.
-
- H. sqrt(1 + x), -1 < x < 1
- This graphs sqrt(1 + x) in the interval -1 < x < 1, and then overlays it
- with the polynomials
- 1
- 1 + x/2
- 1 + x/2 - x^2/8
- 1 + x/2 - x^2/8 + x^3/16
- 1 + x/2 - x^2/8 + x^3/16 - 5x^4/125
- 1 + x/2 - x^2/8 + x^3/16 - 5x^4/125 + 7x^5/256
- The radius of convergence of the Taylor series is 1.
-
- I. sqrt(1 + x), -1 < x < 3
- This graphs sqrt(1 + x) in the interval -1 < x < 3, and then overlays it
- with the polynomials
- 1
- 1 + x/2
- 1 + x/2 - x^2/8
- 1 + x/2 - x^2/8 + x^3/16
- 1 + x/2 - x^2/8 + x^3/16 - 5x^4/125
- 1 + x/2 - x^2/8 + x^3/16 - 5x^4/125 + 7x^5/256
- The radius of convergence of the Taylor series is 1, but the function sqrt(1+x)
- is defined for all x > -1. This is a good way of graphically demonstrating that
- a function may a have a Taylor expansion valid in a smaller domain than the
- function is defined. The interval of convergence is shown on the screen and it
- is easy to see that for x outside this interval the approximation becomes worse
- as the number of terms increases.
-
- J. log(1 + x), -2 < x < 2
- This graphs log(1 + x) in the interval -2 < x < 2, and then overlays it
- with the polynomials
- x
- x - x^2/2
- x - x^2/2 + x^3/3
- x - x^2/2 + x^3/3 - x^4/4
- x - x^2/2 + x^3/3 - x^4/4 + x^5/5
- x - x^2/2 + x^3/3 - x^4/4 + x^5/5 - x^6/6
- The radius of convergence of the Taylor series is 1, but the function log(1+x)
- is defined for all x > -1. This is a good way of graphically demonstrating that
- a function may a have a Taylor expansion valid in a smaller domain than the
- function is defined. The interval of convergence is shown on the screen and it
- is easy to see that for x > 1, the approximation becomes worse as the number of
- terms increases, as distinct from what happens for -1 < x < 1.
-
- When you have finished reading this document, press Q to quit.
-