首页 | 本学科首页   官方微博 | 高级检索  
     


A Leibniz differentiation formula for positive operators
Authors:Chris Impens  Ioan Gavrea
Affiliation:a Department of Pure Mathematics and Computer Algebra, University of Gent, Galglaan 2, B-9000 Gent, Belgium
b Department of Mathematics, Technical University of Cluj-Napoca, RO-3400 Cluj-Napoca, Romania
Abstract:Is is shown that for n→+∞ the Leibnizian combination Ln(fg)−fLn(g)−gLn(f) converges uniformly to zero on a compact interval W if the positive operators Ln belong to a certain class (including Bernstein, Gauss-Weierstrass and many others), and if the moduli of continuity of f,g satisfy ωW(f;h)ωW(g;h)=o(h) as h→0+. A counterexample shows that Lipschitz conditions are not appropriate to bring about a second-order version of this formula.
Keywords:Positive linear operator   Exponential-type operator   Lipschitz classes
本文献已被 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号