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Author: Tinku Tara

Prove-that-the-following-identity-holds-Z-i-1-1-3-3-pi-9-2-1-3-2-5-4-3-27-8-3-4-6-Where-Z-i-a-bi-a-b-Z-denote

Question Number 222937 by Nicholas666 last updated on 11/Jul/25 $$ \\ $$$$\:\:\:\:\mathrm{Prove}\:\mathrm{that}\:\mathrm{the}\:\mathrm{following}\:\mathrm{identity}\:\mathrm{holds}\::\:\:\:\: \\ $$$$\:\:\:\underset{\lambda\in\mathbb{Z}\left[{i}\right]} {\sum}\:\left(\frac{\mathrm{1}}{\left(\mathrm{1}\:+\:\mathrm{3}\lambda\right)^{\mathrm{3}} }\right)\:=\:\frac{\pi^{\mathrm{9}/\mathrm{2}} \:\sqrt{\mathrm{1}\:+\:\sqrt{\mathrm{3}\:}}}{\mathrm{2}^{\mathrm{5}/\mathrm{4}} \:\:\mathrm{3}^{\mathrm{27}/\mathrm{8}} \:\Gamma\left(\frac{\mathrm{3}}{\mathrm{4}}\right)^{\mathrm{6}} \:}\:\:\:\:\: \\ $$$$\:\:\:\:\mathrm{Where}\:\mathbb{Z}\left[{i}\right]\:=\:\left\{{a}\:+\:{bi}\::\:{a},{b}\:\in\:\mathbb{Z}\right\}\:\mathrm{denotes}\:\mathrm{gaussian}\:\mathrm{integers}\:!\:\:\:\:\:\:\:\:\: \\ $$$$\: \\…

Question-222908

Question Number 222908 by Nicholas666 last updated on 10/Jul/25 Answered by Ak090 last updated on 10/Jul/25 $${d}/{dx}\:{ln}\left({cosh}\:{x}\right)\:=\:{tanh}\:{x} \\ $$$${d}/{dx}\:^{{p}} \sqrt{{x}}\:\mathrm{using}\:\mathrm{the}\:\mathrm{formula}\:{d}/{dx}\:{f}^{−\mathrm{1}} \left({x}\right) \\ $$$$=\:\mathrm{1}/{f}'\left({f}^{−\mathrm{1}} \left({x}\right)\right)\:=\:\mathrm{1}/{px}^{\left({p}−\mathrm{1}\right)/{p}} \\…