Radius of starlikeness of convex combinations of univalent starlike functions
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- by D. H. Hamilton and P. D. Tuan PDF
- Proc. Amer. Math. Soc. 78 (1980), 56-58 Request permission
Abstract:
The radius of starlikeness of the convex combination \[ tf(z) + (1 - t)g(z),\quad 0 < t < 1,\] where $f(z)$ and $g(z)$ are normalized univalent starlike functions, is ${r_u} = 0.4035 \ldots$, the positive root of the equation ${r^6} + 5{r^4} + 79{r^2} - 13 = 0$.References
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Additional Information
- © Copyright 1980 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 78 (1980), 56-58
- MSC: Primary 30C45
- DOI: https://doi.org/10.1090/S0002-9939-1980-0548084-1
- MathSciNet review: 548084