What is the fractional derivative of exp(-x) * (x^-1)?

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Discussion Overview

The discussion revolves around the concept of fractional derivatives, specifically the fractional derivative of the function exp(-x) * (x^-1). Participants explore definitions, references, and the existence of fractional derivatives within calculus.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Exploratory

Main Points Raised

  • One participant asks for the fractional derivative of exp(-x) * (x^-1), expressing uncertainty about its definition.
  • Another participant asserts that there is no such thing as fractional derivatives, citing their experience with traditional calculus derivatives.
  • A different participant questions the definition of fractional derivatives being used and suggests researching the topic further.
  • Several references to historical texts and authors who have contributed to the field of fractional calculus are provided, indicating that it is an established area of study.
  • Some participants confirm the existence of fractional derivatives, referencing Wikipedia as a source of information.
  • One participant mentions a historical anecdote about Feynman and fractional calculus, although it is noted as unrelated to the main topic.
  • Another participant reiterates the existence of fractional derivatives and encourages further exploration of the topic.
  • A participant points out that the discussion is somewhat late in addressing the existence of fractional derivatives, suggesting a lack of awareness among some contributors.

Areas of Agreement / Disagreement

There is disagreement among participants regarding the existence and definition of fractional derivatives. Some assert that they exist and provide references, while others maintain that they are not recognized in traditional calculus.

Contextual Notes

Participants express varying levels of familiarity with fractional calculus, and there are references to historical figures and texts that may not be universally known. The discussion reflects a mix of skepticism and acceptance regarding the concept of fractional derivatives.

suku
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what is

d^0.5/(dx)^0.5 {exp(-x)* (x^-1)



tks for any help.
 
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suku said:
what is

d^0.5/(dx)^0.5 {exp(-x)* (x^-1)
tks for any help.

AFAIK there is no such thing. Do you have a text that defines what this is, or are you just asking?

The only derivatives I have ever heard of in working with calculus for many years are the zero-th derivative (the function itself), the first derivative, the second derivative, and so on. No negative order or fractional order derivatives.
 
What definition of fractional derivative are you using?

(If you just came up with the idea yourself, go use google to research "fractional derivative")
 
A few references :

[1] Keith B.Oldham, Jerome Spanier, The Fractional Calculus, Academic Press,
New York, 1974.
[2] Joseph Liouville, Sur le calcul des différentielles à indices quelconques, J. Ecole Polytech., v.13, p.71, 1832.
[3] Bernhard Riemann, Versuch einer allgemeinen auffasung der integration und differentiation, 1847, Re-édit.: The Collected Works of Bernhard Riemann,
Ed. H. Weber, Dover, New York, 1953
[4] Augustin L. Cauchy, Œuvres complètes, 1823, cité par R. Courant, D. Hilbert, Methods of Mathematical Physics, Ed. J.Wiley & Sons, New York, 1962.
[5] Hermann Weyl, Bemerkungen zum begriff des differentialquotienten gebrocherer ordnung, Viertelschr. Naturforsh. Gesellsch., Zürich, v.62, p.296, 1917.
[6] Harry Bateman, Tables of Integral Transforms, Fractional Integrals, Chapt.XIII,
Ed. Mc.Graw-Hill, New-York, 1954.
[8] Jerome Spanier, Keith B.Oldham, An Atlas of Functions, Ed. Harper & Row,
New York, 1987.
[9] Milton Abramowitz, Irene A. Stegun, Handbook of Mathematical Functions, Ed. Dover Pub., New York, 1970.
[10] Jean Jacquelin, Use of Fractional Derivatives to express the properties of Energy Storage Phenomena in electrical networks, Laboratoires de Marcoussis, Route de Nozay, 91460, Marcoussis, 1982.
[11] Oliver Heaviside, Electromagnetic Theory, 1920, re-édit.: Dover Pub., New York, 1950.
From a paper entitled : "La dérivation fractionnaire" (a review for general public, French-style)
http://www.scribd.com/people/documents/10794575-jjacquelin
 
If I remember correctly, I think Feynman was playing with this stuff (without knowing that it was already discovered) when he was still in high school. Just a small bit of trivia and absolutely not related to the purpose of the topic.
 
Mark44 said:
AFAIK there is no such thing. Do you have a text that defines what this is, or are you just asking?

The only derivatives I have ever heard of in working with calculus for many years are the zero-th derivative (the function itself), the first derivative, the second derivative, and so on. No negative order or fractional order derivatives.

Actually this field is a new one.Again not so new, riemann, liouville worked with it. U can google search or get a book on it. It exists really.
 
^You're a couple posts too late.
 

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