3 proofs of 2 well-known theorems on starlike and convex functions
Let f be analytic in D = {z ∈ C : |z| < 1}, and be given by f(z) = z + P∞ n=2 anzn. We give three different proofs for the well-known sharp bounds for the second Hankel determinant |H2(2)(f)| = |a2a4 − a23 | for starlike and convex functions.
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
Penerbit Universiti Kebangsaan Malaysia
2022
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| Online Access: | http://journalarticle.ukm.my/19451/ http://journalarticle.ukm.my/19451/1/Paper-6-Maslina.pdf |
| Summary: | Let f be analytic in D = {z ∈ C : |z| < 1}, and be given by f(z) = z +
P∞
n=2 anzn. We
give three different proofs for the well-known sharp bounds for the second Hankel determinant
|H2(2)(f)| = |a2a4 − a23
| for starlike and convex functions. |
|---|