Radius problems for certain classes of analytic functions

Yao Liang Chung, Maisarah Haji Mohd, Shamani Supramaniam

Abstract


Radius constants for functions in three classes of analytic
functions to be a starlike function of order \(\alpha\), parabolic starlike func-
tion, starlike function associated with lemniscate of Bernoulli, exponen-
tial function, cardioid, sine function, lune, a particular rational function,
and reverse lemniscate are obtained. One of these classes are character-
ized by the condition \(Re g/(ze^z) > 0\). The other two classes are defined
by using the function g and they consist respectively of functions f
satisfying \(Ref/g>0\) and \(|f/g-1| < 1\).


Keywords


Starlike function; radius of starlikeness; exponential function

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References


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DOI: http://dx.doi.org/10.24193/subbmath.2023.4.04

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