SUBORDINATION ON δ-CONVEX FUNCTIONS IN A SECTOR

  • MARJONO, MARJONO (Dept. of Mathematics, University of Brawijaya) ;
  • THOMAS, D.K. (Dept. of Mathematics, University of Wales)
  • 투고 : 2001.03.02
  • 발행 : 2001.07.30

초록

This paper concerns with the subclass of normalized analytic function f in D = {z : |z| < 1}, namely a ${\delta}$-convex function in a sector. This subclass is denoted by ${\Delta}({\delta})$, where ${\delta}$ is a real positive. Given $0<{\beta}{\leq}1$ then for $z{\in}D$, the exact ${\alpha}({\beta},\;{\delta})$ is found such that $f{\in}{\Delta}({\delta})$ implies $f{\in}S^*({\beta})$, where $S^*({\beta})$ is starlike of order ${\beta}$ in a sector. This work is a more general version of the result of Nunokawa and Thomas [11].

키워드

참고문헌

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