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LetS*L(λ) be the class of functionsf, analytic in the unit disc Δ ={z:|z|<1}, with the normalization f(0) =f'(0)-1 = 0, which satisfy the conditionz f'(z)/f(z)≺(1 +z)λ, where≺is the subordination relation. The classS*L(λ) is a subfamily of the known class of strongly starlike functions of order λ. In this paper, the relations between S*L(λ) and other classes geometrically defined are considered. Also, we obtain some characteristics such as, bounds for coefficients, radius of convexity, the Fekete-Szeg ?o inequality, logarithmic coefficients and the second Hankel determinant inequality for functions belonging to this class. The univalent functionsfwhich satisfy the condition <{1 +zf"(z)/f'(z)} < 1 +λ/2, (z∈Δ) are also considered here. [ABSTRACT FROM AUTHOR]

We consider a family of analytic and normalized functions that are related to the domains ℍ(s), with a right branch of a hyperbolas H(s) as a boundary. The hyperbola H(s) is given by the relation 1 ρ = 2 cos ⁡ φ s s (0 < s ≤ 1 , | φ | < (π s) / 2). $\begin{array}{} \frac{1}{\rho}=\left(2\cos\frac{\varphi}{s}\right)^s\quad (0 \lt s\le 1,\, |\varphi| \lt (\pi s)/2). \end{array}$ We mainly study a coefficient problem of the families of functions for which zf′/f or 1 + zf″/f′ map the unit disk onto a subset of ℍ(s). We find coefficients bounds, solve Fekete-Szegö problem and estimate the Hankel determinant. [ABSTRACT FROM AUTHOR]

Let 𝓐 denote the family of analytic functions f with f(0) = f′(0) – 1 = 0, in the open unit disk Δ. We consider a class S c s ∗ (α) := f ∈ A : z f ′ (z) f (z) − 1 ≺ z 1 + α − 1 z − α z 2 , z ∈ Δ , $$\begin{array}{} \displaystyle \mathcal{S}^{\ast}_{cs}(\alpha):=\left\{f\in\mathcal{A} : \left(\frac{zf'(z)}{f(z)}-1\right)\prec \frac{z}{1+\left(\alpha-1\right) z-\alpha z^2}, \,\, z\in \Delta\right\}, \end{array}$$ where 0 ≤ α ≤ 1/2, and ≺ is the subordination relation. The methods and techniques of geometric function theory are used to get characteristics of the functions in this class. Further, the sharp inequality for the logarithmic coefficients γn of f ∈ S c s ∗ $\begin{array}{} \mathcal{S}^{\ast}_{cs} \end{array}$ (α): ∑ n = 1 ∞ γ n 2 ≤ 1 4 1 + α 2 π 2 6 − 2 L i 2 − α + L i 2 α 2 , $$\begin{array}{} \displaystyle \sum_{n=1}^{\infty}\left|\gamma_n\right|^2 \leq \frac{1}{4\left(1+\alpha\right)^2}\left(\frac{\pi^2}{6}-2 \mathrm{Li}_2\left(-\alpha\right)+ \mathrm{Li}_2\left(\alpha^2\right)\right), \end{array}$$ where Li2 denotes the dilogarithm function are investigated. [ABSTRACT FROM AUTHOR]

Let ST L (s) and CV L (s) denote the family of analytic and normalized functions f in the unit disk D : = z : | z | < 1 , such that the quantity z f ′ (z) / f (z) or 1 + z f ″ (z) / f ′ (z) respectively are lying in the region bounded by the limaçon (u − 1) 2 + v 2 − s 4 2 = 4 s 2 u − 1 + s 2 2 + v 2 , where 0 < s ≤ 1 / 2 . The limaçon of Pascal is a curve that possesses properties which qualify it for the several applications in mathematics, statistics (hypothesis testing problem) but also in mechanics (fluid processing applications, known limaçon technology is employed to extract electrical power from low-grade heat, etc.). In this paper we present some results concerning the behavior of f on the classes ST L (s) or CV L (s) . Some appropriate examples are given. [ABSTRACT FROM AUTHOR]