English

Inclusion of generalized Bessel functions in the Janowski class

Complex Variables 2015-06-11 v1

Abstract

Sufficient conditions on AA, BB, pp, bb and cc are determined that will ensure the generalized Bessel functions up,b,c{u}_{p,b,c} satisfies the subordination up,b,c(z)(1+Az)/(1+Bz){u}_{p,b,c}(z) \prec (1+Az)/ (1+Bz). In particular this gives conditions for (4κ/c)(up,b,c(z)1)(-4\kappa/c)({u}_{p,b,c}(z)-1), c0c \neq 0 to be close-to-convex. Also, conditions for which up,b,c(z){u}_{p,b,c}(z) to be Janowski convex, and zup,b,c(z)z{u}_{p,b,c}(z) to be Janowski starlike in the unit disk D={zC:z<1}\mathbb{D}=\{z \in \mathbb{C}: |z|<1\} are obtained.

Keywords

Cite

@article{arxiv.1506.03138,
  title  = {Inclusion of generalized Bessel functions in the Janowski class},
  author = {Saiful R. Mondal and Al Dhuain Mohammed},
  journal= {arXiv preprint arXiv:1506.03138},
  year   = {2015}
}

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13 pages