Abstract
Let the function $f\left( z \right) =z+\sum_{k=2}^{\infty}a{_{k}}z {^{k}}\in A$ be locally univalent for $z \in \mathbb{D}%:=\{z \in \mathbb{C}:{|}z {|}<1\}$ and $0\leq\alpha<1$.Then, $f$\textit{\ }$\in $ $M(\alpha )$ if and only if \begin{equation*}\Re\Big( \left( 1-z ^{2}\right) \frac{f(z )}{z }\Big) >\alpha,\quad z \in \mathbb{D}.\end{equation*}%Due to their geometrical characteristics, this class has a significantimpact on the theory of geometric functions. In the article we obtain sharp bounds for the second Hankel determinant \begin{equation*}\left\vert H_{2}\left( 2\right) \left( f\right) \right\vert =\left\verta_{2}a_{4}-{a_{3}^{2}}\right\vert \end{equation*}and some Toeplitz determinants \begin{equation*}\left\vert {T}_{3}\left( 1\right) \left( f\right) \right\vert =\left\vert 1-2%{a_{2}^{2}}+2{a_{2}^{2}}a_{3}-{a_{3}^{2}}\right\vert,\ \\left\vert {T}_{3}\left( 2\right) \left( f\right) \right\vert =\left\vert {%a_{2}^{3}}-2a_{2}{a_{3}^{2}}+2{a_{3}^{2}}a_{4}-a_{2}{a_{4}^{2}}\right\vert \end{equation*}of a subclass of analytic functions $M(\alpha )$ in the open unit disk $%\mathbb{D}$.
Publisher
Ivan Franko National University of Lviv
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