Document Type : Research Paper


1 Department of Mathematics, Faculty of Science, PNU University, P.O.BOX 19395-4697, Tehran, Iran.

2 Department of Mathematics, Faculty of Science, Urmia University, Urmia, Iran.


In this paper we define a new subclass $S_{LH}(k, \gamma; \varphi)$ of log-harmonic mappings, and then basic properties such as dilations, convexity on one direction and convexity of log functions of convex- exponent product of elements of that class are discussed. Also we find sufficient conditions on $\beta$ such that $f\in S_{LH}(k, \gamma; \varphi)$ leads to $F(z)=f(z)|f(z)|^{2\beta}\in S_{LH}(k, \gamma, \varphi)$. Our results generalize the analogues of the earlier works in the combinations of harmonic functions.


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