Mathematica Eterna
Open Access

Abstract

First order differential subordination for functions with one rotation which have positive real part

Jinjing Qiao and Qiannan Guo

Sharp estimates on β are determined so that p(z) is subordinate to some well known starlike functions P(z) with Re e iθ0P(z) > 0 for some θ0 ∈ [0, 2π], whenever 1 + βzp′ (z) is subordinate to e−iθ0 √ 1+z+i sin θ0 cos θ0 .