the norm estimates of preschwarzian derivatives of spirallike functions and uniformly convex α-spirallike functions

For a constant α∈(−π/2,π/2), we definea subclass of the spirallike functions, spp(α), the setof all functions f∈a re{e−iαzf′(z)f(z)}≥∣∣∣zf′(z)f(z)−1∣∣∣. in the present paper, we shall give the estimate of the norm of the pre-schwarzian derivative tf=f′′/f′ where ∥tf∥=supz∈δ(1−|z|2)|tf(z)| for the functions in spp(α).