Is this a graph of a delta function?

AI Thread Summary
The discussion revolves around sketching the function g(x) = δ(y+a) + δ(y) + δ(y-a), which involves delta functions. Participants express uncertainty about the nature of delta functions, noting that they are not traditional functions and cannot be plotted in the usual sense. The delta function is described as having an infinitely high vertical line at specific points, representing its behavior at y = -a, 0, and a. There is confusion regarding the distinction between delta functions and Kronecker delta functions. Ultimately, the conclusion is that while delta functions cannot be graphically represented in a conventional way, a rough sketch can be made with vertical lines at the specified points.
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Homework Statement


My question asks me to sketch the following:
g(x) = \delta (y+a) + \delta (y) + \delta (y-a)


Homework Equations





The Attempt at a Solution


delta.jpg


I think this is it, but am I correct? I don't recall actually seeing a delta function other than a Kronicker(sp?) delta function, and I'm pretty sure that this isn't one of that type. Research on the web therefore leads me to this (because after trawling my notes I can't actually find anything about it in the entire course!).
 
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another delta function is such a function that integral of d(x)f(x)dx is f(0), and defined like this it can't really be plotted.
 
Well, except that those aren't infinitely tall! Actually, I don't think that is a very good question because the "delta function" isn't a true "function" and doesn't have a graph. A rough "physicist's" idea of the graph of a delta function \delta(x) would be an infinitely high vertical line at x= 0. Since this is in "precalculus", your three (infinitely high) vertical lines at -a, 0, and a are what I would guess are intended here.
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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