# Can we ask question by referring the equations, say, in an article in Wikipedia?

I was reading about "Poisson summation formula" in Wikipedia, yet there is something I can't understand. So can I copy the link and say I did not understand this and this in that link?

It seems wrong because I don't remember seeing such questions but if it is ok, easier.

• Usually,1 it should be relatively easy to copy a formula from Wikipedia. This might browser-dependent, but probably already selecting the formula and trying to copy-paste will give you a format suitable to use here. But what should work reliably is viewing the source (by clicking on edit), finding the formula there and copying it. For example, in the article you mentioned you can find this: \sum_{n=-\infty}^\infty f(n)=\sum_{k=-\infty}^\infty \hat f\left(k\right). Exactly the same syntax works here: $$\sum_{n=-\infty}^\infty f(n)=\sum_{k=-\infty}^\infty \hat f\left(k\right).$$
1For simple and inline formulas, you will often find some combination of HTML and Wikipedia syntax, like here: L<sup>1</sup>('''R'''). So this only works for formulas enclosed in $...$.