An Extension of Rasa's Conjecture to q-Monotone Functions

被引:13
作者
Abel, Ulrich [1 ]
Leviatan, Dany [2 ]
机构
[1] TH Mittelhessen, Fachbereich MND, Wilhelm Leuschner Str 13, D-61169 Friedberg, Germany
[2] Tel Aviv Univ, Raymond & Beverly Sackler Sch Math Sci, IL-6139001 Tel Aviv, Israel
关键词
Inequalities for polynomials; functional inequalities including convexity; CONVEXITY PROBLEM; OPERATORS;
D O I
10.1007/s00025-020-01308-y
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
We extend an inequality involving the Bernstein basis polynomials and convex functions on [0, 1]. The inequality was originally conjectured by Rasa about thirty years ago, but was proved only recently. Our extension provides an inequality involving q-monotone functions, q is an element of N. In particular, 1-monotone functions are nondecreasing functions, and 2-monotone functions are convex functions. In general, q-monotone functions on [0, 1], for q >= 2, possess a (q - 2)nd derivative in (0, 1), which is convex there. We also discuss some other linear positive approximation processes.
引用
收藏
页数:13
相关论文
共 12 条
[1]   A SHARPENING OF A PROBLEM ON BERNSTEIN POLYNOMIALS AND CONVEX FUNCTIONS [J].
Abel, Ulrich ;
Rasa, Ioan .
MATHEMATICAL INEQUALITIES & APPLICATIONS, 2018, 21 (03) :773-777
[2]   An inequality involving Bernstein polynomials and convex functions [J].
Abel, Ulrich .
JOURNAL OF APPROXIMATION THEORY, 2017, 222 :1-7
[3]  
Agratini O., 2004, FACTA U SERIES MATH, V9, P53
[4]   A GENERALIZATION OF KANTOROVICH OPERATORS FOR CONVEX COMPACT SUBSETS [J].
Altomare, Francesco ;
Cappelletti Montano, Mirella ;
Leonessa, Vita ;
Rasa, Ioan .
BANACH JOURNAL OF MATHEMATICAL ANALYSIS, 2017, 11 (03) :591-614
[5]  
BASKAKOV VA, 1957, DOKL AKAD NAUK SSSR+, V113, P249
[6]   ON A CONVEXITY PROBLEM WITH APPLICATIONS TO MASTROIANNI TYPE OPERATORS [J].
Gavrea, Bogdan .
MATHEMATICAL INEQUALITIES & APPLICATIONS, 2020, 23 (02) :765-773
[7]   On a convexity problem in connection with some linear operators [J].
Gavrea, Bogdan .
JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS, 2018, 461 (01) :319-332
[8]   A SHARPENING OF A PROBLEM ON BERNSTEIN POLYNOMIALS AND CONVEX FUNCTIONS AND RELATED RESULTS [J].
Komisarski, Andrzej ;
Rajba, Teresa .
MATHEMATICAL INEQUALITIES & APPLICATIONS, 2018, 21 (04) :1125-1133
[9]   Muirhead inequality for convex orders and a problem of I. Rasa on Bernstein polynomials [J].
Komisarski, Andrzej ;
Rajba, Teresa .
JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS, 2018, 458 (01) :821-830
[10]  
Lorentz G. G., 1953, American Mathematical Soc., V8