LAUSR

Several subclasses of starlike functions are associated with regions in the right half plane of the complex plane, like half-plane, disks, sectors, parabolas and lemniscate of Bernoulli. For a normalized analytic function f defined on the open unit disk ???? belonging to certain well-known classes of functions associated with the above regions, we investigate the radius ρ such that, for the function F(z) = f(ρz)/ρ, zF′(z)/F(z) lies in the lune defined by {w ∈ ℂ : |w2 − 1| < 2|w|} for all z ∈ ????.