都俊杰,秦 川,鄒發(fā)偉,李小飛
(1.長江大學工程技術(shù)學院,中國 荊州 434020; 2.長江大學信息與數(shù)學學院,中國 荊州 434000;3.澳門大學科技學院,中國 澳門 519040)
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由微分從屬和卷積定義的解析函數(shù)類的包含性質(zhì)
都俊杰1*,秦川1,鄒發(fā)偉1,李小飛2,3
(1.長江大學工程技術(shù)學院,中國 荊州434020; 2.長江大學信息與數(shù)學學院,中國 荊州434000;3.澳門大學科技學院,中國 澳門519040)
摘要本文由微分從屬和卷積定義了在單位圓盤U={z∈C:|z|<1}內(nèi)的三類單葉解析函數(shù)類Pa1,…,aq;b1,…,bs(μ,h,λ),Ta1,…,aq;b1,…,bs(μ,h,α),Ra1,…,aq;b1,…,bs(μ,h,α),并利用從屬性質(zhì)和凸函數(shù)的理論,研究得到了它們的包含關(guān)系.
關(guān)鍵詞從屬;卷積;包含性質(zhì);星象函數(shù);凸函數(shù)
記N表示由單位圓盤U內(nèi)的單葉解析凸的函數(shù)h(z)組成的正實部函數(shù)類,即滿足Re{h(z)}>0.Ozkan和Altintas[1]定義了下面的函數(shù)類:
Ra(h,α):={f:(ka*f)′(z)+αz(ka*f)″(z) Ra,c(h,α):={f:(L(a,c)f)′(z)+αz(L(a,c)f)″(z) Ra1,…,aq;b1,…,bs(h,α):={f:(H1(a1,…,aq;b1,…,bs)f)′(z)+αz(H1(a1,…,aq;b1,…,bs)f)″(z) z(hμ(a1,…,aq;b1,…,bs;z)*f(z))′=hμ(a1,…,aq;b1,…,bs;z)*zf′(z), (1) hμ(a1,…,aq;b1,…,bs;z)*z2f″(z)=z2(Hμq,s(a1,…,aq;b1,…,bs)f)″(z). (2) h(z),f∈A,z∈U},0≤λ≤1;h∈N; (3) h(z),f∈A,z∈U},α≥0;h∈N; (4) h(z),f∈A,z∈U},α≥0;h∈N. (5) 本文利用從屬性質(zhì)與凸函數(shù)的理論,研究得到上述函數(shù)類的包含性質(zhì). 1基本引理 引理2[12]設(shè)0<α≤β,若β≥2或α+β≥3,則 引理3[13]若f(z)∈K,g(z)∈S*,則對于U內(nèi)任意解析函數(shù)h(z),都有 2主要結(jié)論 定理1設(shè)g(z)=λzf′(z)+(1-λ)f(z),則f(z)∈Pa1,…,aq;b1,…,bs(μ,h,λ)當且僅當g(z)∈Pa1,…,aq;b1,…,bs(μ,h,0). 證利用(1)、(2)式,得 因此,g(z)∈Pa1,…,aq;b1,…,bs(μ,h,0).反過來,若g(z)∈Pa1,…,aq;b1,…,bs(μ,h,0),按同樣的方法容易得到f(z)∈Pa1,…,aq;b1,…,bs(μ,h,λ). 證設(shè)f(z)∈Pa1,…,aq;b1,…,bs(μ,h,λ),zφ′(z)=λzf′(z)+(1-λ)f(z)=g(z),由于g(z)∈Pa1,…,aq;b1,…,bs(μ,h,0),故zφ′(z)∈Pa1,…,aq;b1,…,bs(μ,h,0).經(jīng)計算,得 因此,φ(z)=Pa1,…,aq;b1,…,bs(μ,h,1). 定理3若f(z)∈Ta1,…,aq;b1,…,bs(μ,h,α),則f(z)∈Ta1,…,aq;b1,…,bs(μ,h,0). 定理4若α>β≥0,f(z)∈Ta1,…,aq;b1,…,bs(μ,h,α),則f(z)∈Ta1,…,aq;b1,…,bs(μ,h,β). 證當β=0時,由定理3容易得到結(jié)論.當β>0時,設(shè)f(z)∈Ta1,…,aq;b1,…,bs(μ,h,α),由函數(shù)類的定義和從屬性質(zhì)知 故f(z)∈Ta1,…,aq;b1,…,bs(μ,h,β). 定理5若f(z)∈Ra1,…,aq;b1,…,bs(μ,h,α),則f(z)∈Ra1,…,aq;b1,…,bs(μ,h,0). 定理6若α>β≥0,f(z)∈Ra1,…,aq;b1,…,bs(μ,h,α),則f(z)∈Ra1,…,aq;b1,…,bs(μ,h,β). 證當β=0時,由定理5容易得到結(jié)論.當β>0時,設(shè)f(z)∈Ra1,…,aq;b1,…,bs(μ,h,α),由函數(shù)類的定義和從屬性質(zhì)知 故f(z)∈Ra1,…,aq;b1,…,bs(μ,h,β). 定理7f(z)∈Ra1,…,aq;b1,…,bs(μ,h,α)?zf′(z)∈Ta1,…,aq;b1,…,bs(μ,h,α), (6) Ra1,…,aq;b1,…,bs(μ,h,α)?Ta1,…,aq;b1,…,bs(μ,h,α). (7) 證由函數(shù)類的定義和式(5)、(6)并經(jīng)計算得 上式意味著式(6)成立.設(shè)f(z)∈Ra1,…,aq;b1,…,bs(μ,h,α),并令 證設(shè)f(z)∈Pa1,…,aq;b1,…,bs(μ,h,λ),則存在Schwarz函數(shù)w(z)使得 h(w(z)). 即f(z)∈Pa1,…,aq;b1,…,bs(μ,h,λ). 參考文獻: [1]OZKAN O, ALTNTAS O. Applications of differential subordination [J]. Appl Math Lett, 2006,19(3):728-734. [2]TROJNAR-SPELINA L. On certain applications of the Hadamard product [J]. Appl Math Comput, 2008, 199(4):653-662. [3]EL-ASHWAH R M, AOUF M K, ABD-ELTWAB A M. On certain classes ofp-valent functions invoving Dziok-Srivastava operator [J]. Acta Univ Apulensis, 2013,35(2):203-210. [4]XU Q H, XIAO H G, SRIVASTAVA H M. Some applications of differential subordination and the Dziok-Srivastava convolution operator [J]. Appl Math Comput, 2014, 230(3):496-508. [5]SEOUDY T M, AOUF M K. Inclusion properties for some subclasses of analytic functions associated with generalized integral operator [J]. J Egypt Math Soc, 2013,21(3):11-15. [6]KWON O S, CHO N E. Inclusion properties for certain subclasses of analytic functions associated with the Dziok-Srivastava operator [J]. J Inequal Appl, 2007,35(4):1-10. [7]劉竟成,張學軍.Cn中單位球上Bergman型空間的一種積分算子[J].數(shù)學年刊A輯, 2013,34(3):257-268. [8]李小飛,嚴證.某類積分算子解析函數(shù)的性質(zhì)[J].湖南師范大學自然科學學報, 2013,36(4):11-15. [9]田琳,韓紅偉.算子解析函數(shù)的系數(shù)不等式[J].數(shù)學的實踐與認識, 2014,44(18):239-245. [11]MILLER S S, MOCANU P T. Differential subordinations: theory and applications, series on monographs and textbooks in pure and applied mathematics [M]. New York: Marcel Dekker Incorporation, 2000. [12]RUSCHEWEYH S. Convolutions in geometric function theory [M]. Montreal: Les Presses de l’Universite de Montreal, 1982. [13]RUSCHEWEYH S, SHEIL-SMALL T. Hadamard product of schlicht functions and the polya-schoenberg conjecture [J].Comment Math Helv, 1973,48(4):119-135. (編輯HWJ) Inclusion Properties for Subclasses of Analytic Functions Defined by Differential Subordination and Convolution DUJun-jie1*,QINChuan1,ZOUFa-wei1,LIXiao-fei2,3 (1.College of Engineering and Technology, Yangtze University, Jingzhou 434020, China;2.School of Information and Mathematics, Yangtze University, Jingzhou 434020, China;3.College of Science and Technology, University of Macau, Macau, 519040, China) AbstractIn this article, we define three subclasses of analytic functions Pa1,…,aq;b1,…,bs(μ,h,λ),Ta1,…,aq;b1,…,bs(μ,h,α),Ra1,…,aq;b1,…,bs(μ,h,α) by using of differential subordination and convolution in the open disc U={z∈C:|z|<1}. Inclusion properties of these subclasses are obtained by employing properties of subordination and theories of convex functions. Key wordssubordination; convolution; inclusion properties; starlike function; convex function 中圖分類號O174.51 文獻標識碼A 文章編號1000-2537(2016)02-0077-05 *通訊作者,E-mail:29149875@qq.com 基金項目:湖北省自然科學基金資助項目(2013CFAO053);湖北省教育廳科研基金資助項目(B2013281);長江大學科研基金資助項目(2013cjy01);長江大學工程技術(shù)學院科技創(chuàng)新基金資助項目(2015J0802) 收稿日期:2015-11-12 DOI:10.7612/j.issn.1000-2537.2016.02.013