The functional |c₄ + pc₂c₃ + qc³₂| is considered in the class of all univalent holomorphic functions in the unit disk. For real values p and q in some regions of the (p,q)-plane the estimates of this functional are obtained by the area method for univalent functions. Some new regions are found where the Koebe function is extremal.
@article{bwmeta1.element.bwnjournal-article-apmv63z1p7bwm,
author = {Larisa Gromova and Alexander Vasil'ev},
title = {On the estimate of the fourth-order homogeneous coefficient functional for univalent functions},
journal = {Annales Polonici Mathematici},
volume = {63},
year = {1996},
pages = {7-12},
zbl = {0844.30010},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-apmv63z1p7bwm}
}
Larisa Gromova; Alexander Vasil'ev. On the estimate of the fourth-order homogeneous coefficient functional for univalent functions. Annales Polonici Mathematici, Tome 63 (1996) pp. 7-12. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-apmv63z1p7bwm/
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