OMS-Vol. 2 (2018), Issue 1, pp. 266–286
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Abdussalam Eghbiq, Maslina Darus
Abstract:In this paper, we introduce and study the classes \(S_{n,\mu}(\gamma,\alpha,\beta,\) \(\lambda,\nu,\varrho,\mho)\) and \(R_{n,\mu}(\gamma,\alpha,\beta,\lambda,\nu,\varrho,\mho)\) of functions \(f\in A(n)\) with \((\mu)z(D^{\mho+2}_{\lambda,\nu,\varrho}(\alpha,\omega)f(z))^{‘} \) \(+(1-\mu)z(D^{\mho+1}_{\lambda,\nu,\varrho}(\alpha,\omega)f(z))^{‘}\neq0\), where \(\nu>0,\varrho,\omega,\lambda,\alpha,\mu \geq0, \mho\in N_{0}, z\in U\) and \(D^{\mho}_{\lambda,\nu,\varrho}(\alpha,\omega)f(z):A(n)\longrightarrow A(n),\) is the linear differential operator, newly defined as
\( D^{\mho}_{\lambda,\nu,\varrho}(\alpha,\omega)f(z)=z-\sum_{k=n}^{\infty}\left( \dfrac{\nu+k(\varrho+\lambda)\omega^{\alpha}}{\nu} \right)^{\mho} a_{k+1}z^{k+1}. \)
Several properties such as coefficient estimates, growth and distortion theorems, extreme points, integral means inequalities and inclusion relation for the functions included in the classes \(S_{n,\mu} (\gamma,\alpha,\beta,\lambda,\nu,\varrho,\mho,\omega)\) and \(R_{n,\mu}(\gamma,\alpha,\beta,\lambda,\nu,\varrho,\mho,\omega)\) are given.