2 days ago · Mathematics Stack Exchange is a platform for asking and answering questions on mathematics at all levels.

Oct 7, 2020 · Show that (Un) is bounded, convergent and find its limit. To prove that the sequence is bounded i intuitively used the fixed point theorem because at first glance i don't really know the …

Nov 12, 2015 · J. P. Aubin, Un théorème de compacité, C.R. Acad. Sc. Paris, 256 (1963), pp. 5042–5044. It seems this paper is the origin of the "famous" Aubin–Lions lemma. This lemma is …

Jun 4, 2012 · A remark: regardless of whether it is true that an infinite union or intersection of open sets is open, when you have a property that holds for every finite collection of sets (in this case, the union …

Jun 24, 2015 · By un-integrable I mean functions whose antiderivative can not be expressed in terms of elementary functions. I recently learnt that any differentiable function can be expanded using the …

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Dec 21, 2016 · Limit sequence (Un) and (Vn) Ask Question Asked 9 years, 2 months ago Modified 9 years, 2 months ago

Nov 11, 2018 · The Integration by Parts formula may be stated as: $$\\int uv' = uv - \\int u'v.$$ I wonder if anyone has a clever mnemonic for the above formula. What I often do is to derive it from the …

Apr 10, 2015 · Saying that 1 divided by 0 is undefined, does not mean that you can carry out the division and that the result is some strange entity with the property “undefined”, but simply that dividing 1 by 0 …

When can we say a multiplicative group of integers modulo $n$, i.e., $U_n$ is cyclic? $$U_n=\\{a \\in\\mathbb Z_n \\mid \\gcd(a,n)=1 \\}$$ I searched the internet but ...