Información del autor
Documentos disponibles escritos por este autor (38)
Añadir el resultado a su cesta Hacer una sugerencia Refinar búsqueda
texto impreso
Muñoz-Fernández, Gustavo A. ; Sarantopoulos, Yannis ; Seoane-Sepúlveda, Juan B. | Heldermann Verlag | 2008Given a trinomial of the form p(x) = ax(m) + bx(n) + c with a, b, c is an element of R, we obtain, explicitly, the best possible constant M.,,(x) in the inequality vertical bar p'(x)vertical bartexto impreso
Bernstein-markov type inequalities and other interesting estimates for polynomials on circle sectors
Jiménez Rodríguez, Pablo ; Muñoz-Fernández, Gustavo A. ; Pellegrine, D. ; Seoane-Sepúlveda, Juan B. | Board | 2017In this paper we study various polynomial inequalities for 2-homogeneous polynomials on the circular sector {rei: r ? [0,1]? [0, 2]}. In particular, we obtain sharp Bernstein and Markov inequalities for such polynomials, we calculate the polariz[...]texto impreso
Gámez Merino, José Luis ; Muñoz-Fernández, Gustavo A. ; Pellegrino, Daniel ; Seoane-Sepúlveda, Juan B. | Elsevier Science | 2012-01In this paper we prove a characterization of continuity for polynomials on a normed space. Namely, we prove that a polynomial is continuous if and only if it maps compact sets into compact sets. We also provide a partial answer to the question a[...]texto impreso
Gámez Merino, José Luis ; Muñoz-Fernández, Gustavo A. ; Seoane-Sepúlveda, Juan B. | Mathematical Assoc Amer | 2011-02It is well known that a function f : R -> R is continuous if and only if the image of every compact set under f is compact and the image of every connected set is connected. We show that there exist two 2(c)-dimensional linear spaces of nowhere[...]texto impreso
In this paper we find an alternative description of the Bochnak complexification of a real Hilbert space. This new interpretation of the Bochnak norm lets us give a characterization of a real inner product space.texto impreso
In 1951 V. Jarnik constructed two continuous functions whose Volterra convolution is nowhere differentiable. We generalize Jarnik's results by proving that the set of such functions is maximal lineable. This would shed some light on a question p[...]texto impreso
Araujo, G. ; Jiménez Rodríguez, P. ; Muñoz-Fernández, Gustavo A. ; Seoane-Sepúlveda, Juan B. | Elsevier | 2017In this paper, equivalence constants between various polynomial norms are calculated. As an application, we also obtain sharp values of the Hardy Littlewood constants for 2-homogeneous polynomials on l(p)(2) spaces, 2texto impreso
Muñoz-Fernández, Gustavo A. ; Pellegrino, D. ; Seoane-Sepúlveda, Juan B. | Taylor & Francis | 2012-05A classical inequality due to H. F. Bohnenblust and E. Hille states that for every positive integer n there is a constant C-n > 0 so that (Sigma(N)(i1,...,in=1) vertical bar U(e(i1), . . . , e(in))vertical bar(2n/n+1))(n+1/2n) C. The origina[...]texto impreso
A mapping phi : [-1, 1] -> [0, infinity) is a curved majorant for a polynomial p in one real variable if vertical bar p(x)vertical bartexto impreso
For each pair of numbers m, n epsilon N with m > n, we consider the norm on R-3 given by parallel to(a, b, c)parallel to m,n = sup{vertical bar ax(m) +bx(n) +C vertical bar: x epsilon [-1, 1]} for every (a, b, c) epsilon R-3. We investigate som[...]texto impreso
Muñoz-Fernández, Gustavo A. ; Revesz, Szilard Gy. ; Seoane-Sepúlveda, Juan B. | Matematisk Inst | 2009If Delta stands for the region enclosed by the triangle in R(2) of vertices (0, 0), (0, 1) and (1, 0) (or simplex for short), we consider the space P((2)Delta) of the 2-homogeneous polynomials on R(2) endowed with the norm given by parallel to a[...]texto impreso
Fenoy, Mar ; Gámez Merino, José Luis ; Muñoz-Fernández, Gustavo A. ; Sáez Maestro, Eva | De Gruyter Open Ltd | 2017This expository paper focuses on the study of extreme surjective functions in ??. We present several different types of extreme surjectivity by providing examples and crucial properties. These examples help us to establish a hierarchy within the[...]texto impreso
Jiménez Rodríguez, P. ; Maghsoudi, S. ; Muñoz-Fernández, Gustavo A. ; Seoane-Sepúlveda, Juan B. | Belgian Mathematical Soc Triomphe | 2016It is known that there is not a two dimensional linear space in R-R every non-zero element of which is an injective function. Here, we generalize this result to arbitrarily large dimensions. We also study the convolution of non differentiable fu[...]texto impreso
We give a condition for a family of functions to be lineable by means of its additivity. The novelty presented here is that we solve the lineability problem using a technique that is not constructive, as are most approaches to this problem. We r[...]texto impreso
Araujo, G. ; Bernal-González, L. ; Muñoz-Fernández, Gustavo A. ; Prado-Bassas, J. A. ; Seoane-Sepúlveda, Juan B. | Polish Acad Sciencies Inst Mathematics | 2017We prove the existence of large algebraic structures - including large vector subspaces or infinitely generated free algebras - inside, among others, the family of Lebesgue measurable functions that are surjective in a strong sense, the family o[...]
