Landau's theorem for planar harmonic mappings
نویسنده
چکیده
Landau gave a lower estimate for the radius of a schlicht disk centered at the origin and contained in the image of the unit disk under a bounded holomorphic function f normalized by f(0) = f ′(0)− 1 = 1. Chen, Gauthier, and Hengartner established analogous versions for bounded harmonic functions. We improve upon their estimates.
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ورودعنوان ژورنال:
- Computers & Mathematics with Applications
دوره 57 شماره
صفحات -
تاریخ انتشار 2009