Can Any Function Satisfy a General Integral Equation?

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    General Integral
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Discussion Overview

The discussion revolves around the question of whether there exists any function for which the integral from negative infinity to positive infinity yields an integer value other than 0 or infinity. The scope includes theoretical exploration of integral equations and properties of functions.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant questions if there exists a function such that the integral from -∞ to ∞ is any integer except 0 and ∞.
  • Another participant suggests that an impulse function could serve as such a function.
  • A different participant proposes that the function f(x) = 1/(1+x^2) does not yield 0 or ∞ for its integral.
  • It is noted that an impulse function satisfies the condition of the integral equaling 1, but it is not classified as a traditional function.
  • A participant provides an example of a function, f(x) = (7/√π)e^(-x²), stating that its integral equals 7, indicating that many such functions exist.
  • Participants express interest and curiosity about the properties of these functions and the integrals involved.

Areas of Agreement / Disagreement

Participants do not reach a consensus; multiple competing views and examples are presented regarding the types of functions that can satisfy the integral condition.

Contextual Notes

Some participants express uncertainty about the definitions and properties of the functions discussed, particularly regarding the impulse function and its classification.

Who May Find This Useful

This discussion may be of interest to those exploring integral equations, properties of functions in mathematical analysis, or the conceptual understanding of impulse functions.

Vorde
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Is there any function such that:
[itex]_{-∞}[/itex][itex]\int[/itex][itex]^{∞}[/itex]f(x) dx
Is any integer except 0 and ∞?
 
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f(x) can be impulse function
 
I'm not sure what omkar meant by impulse function but if f(x)=[itex]\frac{1}{1+x^2}[/itex], the integral will not equal 0 or ∞.
 
I looked it up, apparently is an equation that satisfies the statement that the integral from -∞ to ∞ is 1, but because of the way it's defined it isn't actually a function.
 
Vorde said:
Is there any function such that:
[itex]_{-∞}[/itex][itex]\int[/itex][itex]^{∞}[/itex]f(x) dx
Is any integer except 0 and ∞?


There are an infinite number of such functions. For example:
[tex]\int^\infty_{-\infty}e^{-x^2}dx = \sqrt{\pi}[/tex]
so if:
[tex]f(x) = \frac{7}{\sqrt\pi}e^{-x^2}[/tex]
then:
[tex]\int^\infty_{-\infty}f(x)dx = 7[/tex]
There are lots of functions like this that one can play this game with.
 
Vorde said:
I looked it up, apparently is an equation that satisfies the statement that the integral from -∞ to ∞ is 1, but because of the way it's defined it isn't actually a function.

Ohhhh. That is very interesting. This is the first time I have ever heard of that.

phyzguy said:
There are an infinite number of such functions. For example:
[tex]\int^\infty_{-\infty}e^{-x^2}dx = \sqrt{\pi}[/tex]
so if:
[tex]f(x) = \frac{7}{\sqrt\pi}e^{-x^2}[/tex]
then:
[tex]\int^\infty_{-\infty}f(x)dx = 7[/tex]
There are lots of functions like this that one can play this game with.

Cool! That looks fun lol.
 

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