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Math Forum » Discussions » sci.math.* » sci.math.independent

Topic: dirac delta function is not a TRUE function??
Replies: 11   Last Post: Jul 19, 2011 11:08 PM

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Tim Little

Posts: 1,793
Registered: 2/7/09
Re: dirac delta function is not a TRUE function??
Posted: Jul 12, 2011 3:55 AM
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On 2011-07-12, MBALOVER <mbalover9@gmail.com> wrote:
> Thanks Gerry. But I am still confused. I think at x = 0, delta(x) =
> infinity. If so, y = -log(0) = + infinity too. Is y = - log(x) Not a
> true function?

The expression "-log(x)" can define a true function from R^+ to R, but
does not define a function from R to R.

There are a number of ways to define the Dirac delta "function" (more
strictly, a distribution), but none of them involve "delta(x) = infinity".
Some distributions correspond to real functions, some do not. The
delta distribution is one of those that does not.


--
Tim

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