Acta Mathematica Academiae Scientiarum Hungarica - Tập 168 - Trang 443-453 - 2022
P. Kumar
The Erdős–Lax Theorem states that, if P(z) is a polynomial of degree n having no
zeros in $$|z|<1$$ , then $$\max_{|z|=1}|P'(z)|\leq
\frac{n}{2}\max_{|z|=1}|P(z)|.$$ The problem of generalizing the Erdős–Lax
Theorem to the class of polynomials having no zeros in $$|z|... hiện toàn bộ
Acta Mathematica Academiae Scientiarum Hungarica - Tập 84 - Trang 267-274 - 1999
I. Joó, Nguyen Van Su
This paper is concerned with the null-controllability of the
infinite-dimensional discrete-time linear system described by $$(A, B, \Omega )
x_{n + 1} = Ax_n + Bu_n$$ where xn ∈ X, un ∈ Ω ⊂ U, X and U are Asplund spaces,
A ∈ L(X, X), B ∈ L (U, X), Ω is a convex set, int Ω ≠ 0 and 0 ∈ Ω.