Approximation of analytic functions satisfying a Lipschitz condition.

Approximation of o-minimal maps satisfying a Lipschitz condition

Consider an o-minimal expansion of the real field. We show that definable Lipschitz continuous maps can be definably fine approximated by definable continuously differentiable Lipschitz maps whose Lipschitz constant is close to that of the original map.

Commutators of Singular Integral Operators Satisfying a Variant of a Lipschitz Condition

Let T be a singular integral operator with its kernel satisfying |K(x - y) - ∑(k=1)(ℓ) ‍Bk (x)ϕk(y)| ≤ C| y| (γ)/|x - y| (n+γ), |x | > 2| y| > 0, where B(k) and ϕk (k = 1,…, ℓ) are appropriate functions and γ and C are positive constants. For b = b1'...,bm) with bj ∈ BMO(ℝ(n)), the multilinear commutator Tb generated by T and b is formally defined by T(b)ƒ(x) = ∫(ℝn)[∏(j=1)(m) (b(j)(x) - b(j)(y...

Approximation of Analytic Functions by Chebyshev Functions

and Applied Analysis 3 where we refer to 1.4 for the am’s and we follow the convention ∏m−1 j m · · · 1. We can easily check that cm’s satisfy the following relation: m 2 m 1 cm 2 − ( m2 − n2 ) cm am 2.2 for any m ∈ {0, 1, 2, . . .}. Theorem 2.1. Assume that n is a positive integer and the radius of convergence of the power series ∑∞ m 0 amx m is ρ > 0. Let ρ0 min{1, ρ}. Then, every solution y ...

Approximation of Analytic Functions by Special Functions

We survey the recent results concerning the applications of power series method to the study of Hyers–Ulam stability of differential equations.

Approximation of Analytic Functions by Kummer Functions