Roots of the normal distribution

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Homework Statement


$$f:\mathbb{R} \rightarrow \mathbb{R},$$

$$ f(x) = \frac{1}{\sigma \sqrt{2 \pi}} e^{\frac{-(x-\mu)^2}{2 \sigma ^{2}}}$$

What are the roots of this equation?

Homework Equations

The Attempt at a Solution



The roots of an equation are the values of x such that f(x) = 0. This is the first time I have seen a question like this and am still getting my head around the normal distribution, but as far as I'm aware the curve never does reach f(x) = 0 so I want to express the idea that the roots of this equation are +/- \infty but I don't know how to do this...

lim_{x \rightarrow +/- \infty} f(x) = 0

I'd appreciate some guidance,

thanks :)
 
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It doesn't look to me like you need much guidance on this. You have it exactly correct. But I wouldn't say the roots are ##\pm \infty##. Just say it has no roots but the limit is 0 as you have stated.
 
LCKurtz said:
It doesn't look to me like you need much guidance on this. You have it exactly correct. But I wouldn't say the roots are ##\pm \infty##. Just say it has no roots but the limit is 0 as you have stated.

Well that is good news, thanks!
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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