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Science in China Series A: Mathematics

, Volume 40, Issue 1, pp 1–9 | Cite as

Agard’s η-distortion function and Schottky’s theorem

  • Songliang Qiu
Science in China (Series A)

Abstract

The monotoneity properties of certain functions defined in terms of the η-distortion function ηκ(t) in quasiconformal theory are studied and asymptotically sharp bounds are obtained for ηκ(t), thus proving some properties of the upper bound functionK(t, r) in Schottky’s theorem on analytic functions and improving the known explicit bounds forK (t, r).

Keywords

quasiconformal theory special function Schottky’s theorem 

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Copyright information

© Science in China Press 1997

Authors and Affiliations

  • Songliang Qiu
    • 1
  1. 1.School of Science and ArtsHangzhou Institute of Electronics EngineeringHangzhouChina

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