5:39 AM
The tag was mentioned, for example, here and a few other times.
1 message moved to ­Trash
The oldest occurrences found by those queries are from 2017:
3

Let $L$ be a finite-dimensional Lie algebra over a field of characteristic zero. It is not difficult to see (and also follows from Theorem 4.4 of [G. Hochschild: Semi-simple algebras and generalized derivations, Amer. J. Math. 64, (1942), 677–694]) that the derivation algebra $D(L)$ of $L$ is sim...

0

The final result I draw is related to the integral of modified Bessel function of the second kind. But I can not solve it, and I need a explicit solution Are you willing to help me? Thank all $I = \mathop {\lim }\limits_{x \to 0} \frac{\partial }{{\partial x}}\frac{{{K_0}(a\sqrt x )}}{{{K_0}(b\s... 2 Consider the ring$\mathbb{C}[[X,Y]]$and its subring$\mathbb{C}[[X+iY]]$, where$i=\sqrt{-1}$. One can show that$f(X,Y):=u(X,Y)+iv(X,Y)\in \mathbb{C}[[X,Y]]$lies in$\mathbb{C}[[X+iY]]$iff$u$and$v$satisfy the CR-equations formally. The necessary condition follows by straightforward forma... This question from May 2017 had this tag, but it was removed: Random graphs- Erdos and Renyi 1959 paper. In mathematics, a derivation is a function on an algebra which generalizes certain features of the derivative operator. Specifically, given an algebra A over a ring or a field K, a K-derivation is a K-linear map D : A → A that satisfies Leibniz's law: D ( a b ) = a D ( b ) + D ( a ) b . {\displaystyle D(ab)=aD(b)+D(a)b.} More generally, if M is an A-bimodule, a K-linear map D : A → M that satisfies the Leibniz law is also... On Mathematics, the tag derivations has only 8 questions. At the moment, it doesn't have a tag-info, either. A snapshot of the tag in the Wayback Machine from May 2021. 6:08 AM At the moment, there are 78 questions tagged . I see that the OP edited this question, so that might have lead to the question on meta: Derivative of$X \mapsto X X^T$-4 My goal is to compute this derivative: $$\frac{d(LL^T)}{dL}$$ Where$L$is a lower triangular matrix obtained from a Cholesky decomposition. Is there a way to compute it in a compact form? The question currently has 4 close votes and is in the close votes review. 3 hours later… 9:16 AM Jun 3, 2018 at 8:26, by Martin Sleziak What is the intended meaning of tag . Shouldn't it be either removed or replaced by in the questions that are actually about derivatives? Such as: Partial derivatives of spherical harmonics and Derivative with multiple summation operators. Nov 30, 2018 at 8:00, by Martin Sleziak It's quite likely that the question is going to be closed and deleted. But it is at least an opportunity to remind that the tag derivations has a bit unclear usage. Is it suitable here: Does$f \leq f'$imply$f' \leq f''$? 5 hours later… 2:23 PM My old algebra memory says: a derivation on a ring$R$is a map$D : R \to R$satisfying$D(a+b) = D(a) + D(b)$and$D(ab) = aD(b)+D(a)b$. Perhaps that is what the tag is for. — Gerald Edgar 1 hour ago @GeraldEdgar My concern is that some people might use it for questions on derivatives, i.e., as a synonym for differentiation — Rodrigo de Azevedo 1 hour ago For example, there are 7 questions tagged derivations+real-analysis. 1 I would like to prove a real$C^{\infty}$(polynomial) multivariable function$F : (a_1,a_2,...a_n) \rightarrow (b_1,b_2,...b_n) $is lipchitz of parameter$l$is it sufficient to prove the norm of dominant eigenvalue of$Jacobian(F)$is less than$l$. In other words, is the "spectral radius of ... 16 After this question : Does every real function have this weak continuity property? Natrualy there are an other (more difficult) : Is it true that for every real function$f:\mathbb{R}\to\mathbb{R}$, there exists a real sequence$(x_n)_n$, taking values different from$c$, converging to some... 16 Let$C^\infty$denote the collection of functions$f:\mathbb{R}\to\mathbb{R}$such that for every positive integer$n$, the$n$-th derivative of$f$exists. For$f\in C^\infty$we set$f^{(0)} = f$, and$f^{(n+1)} = \big(f^{(n)}\big)'$for all non-negative integers$n$. Is there$f\in C^\inft...

-2

Let $a> 0, \alpha<0$ and $\beta>0$. How to prove that the function: $$f(x)=\frac{(\Gamma(a)-\Gamma(a,\alpha \ln(\beta x))) (\alpha\ln(x))^a}{(\alpha\ln(\beta x))^a (\Gamma(a)-\Gamma(a,\alpha \ln(x)))},$$ is monotonic. I tried the sign of derivative but is more delicate.

6

I know practically nothing about fractional calculus so I apologize in advance if the following is a silly question. I already tried on math.stackexchange. I just wanted to ask if there is a notion of fractional derivative that is linear and satisfy the following property $D^u((f)^n) = \alpha D^u... 0 I want to prove that a differentiable function$f: [0,\infty) \rightarrow \mathbb{R} $, which satisfies the following condition is always non-negative: Assume$f(0)=0$and whenever$f(a)=0$, then$f'(a) \geq 0$and$f''(a) \neq 0$. Note that if I change the condition to this:$f(0)=0$and whenev... 3 Let$F$be a continuous convex function on$\mathbb{R}^n$. If the subdifferential$\partial F(x)$of$F(x)$admits a continuous selection, for every$x \in \mathbb{R}^n$, does it mean that$F$is differentiable on$ \mathbb{R}^n\$ ? I was trying to use theorem 25.5 and 25.6 (Rockafellar: Convex An...

2 hours later…
4:16 PM
I could also see it getting used for questions about logical derivations, i.e. formal proofs in the sense of natural deduction or similar systems. — Peter LeFanu Lumsdaine 2 hours ago