English

Order of Starlikeness and Convexity of certain integral transforms using duality techniques

Complex Variables 2014-06-26 v1

Abstract

For α0\alpha\geq 0, β<1\beta<1 and γ0\gamma\geq 0, the class Wβ(α,γ)\mathcal{W}_{\beta}(\alpha,\gamma) satisfies the condition \begin{align*} {\rm Re\,} \left( e^{i\phi}\left((1-\alpha+2\gamma)f/z+(\alpha-2\gamma)f'+ \gamma zf''-\beta\right)\frac{}{}\right)>0, \quad \phi\in {\mathbb{R}},{\,}z\in {\mathbb{D}}; \end{align*} is taken into consideration. The Pascu class of ξ\xi-convex functions of order σ\sigma (M(σ,ξ))(M(\sigma,{\,}\xi)), having analytic characterization \begin{align*} {\rm Re\,}\frac{\xi z(zf'(z))'+(1-\xi)zf'(z)}{\xi zf'(z)+(1-\xi)f(z)}>\sigma,\quad 0\leq \sigma< 1,\quad z\in {\mathbb{D}}, \end{align*} unifies starlike and convex functions class of order σ\sigma.The admissible and sufficient conditions on λ(t)\lambda(t) are investigated so that the integral transforms \begin{align*} V_{\lambda}(f)(z)= \int_0^1 \lambda(t) \frac{f(tz)}{t} dt, \end{align*} maps the function from Wβ(α,γ)\mathcal{W}_{\beta}(\alpha,\gamma) into M(σ,ξ)M(\sigma,{\,}\xi). Further several interesting applications, for specific choice of λ(t)\lambda(t) are discussed which are related to the classical integral transform.

Keywords

Cite

@article{arxiv.1406.6471,
  title  = {Order of Starlikeness and Convexity of certain integral transforms using duality techniques},
  author = {Satwanti Devi and A. Swaminathan},
  journal= {arXiv preprint arXiv:1406.6471},
  year   = {2014}
}

Comments

generalization of the previous article