# Criteria for univalence, Integral means and Dirichlet integral for Meromorphic functions

## TL;DR

This paper establishes criteria for univalence of certain meromorphic functions with a pole, and derives exact and sharp bounds for Dirichlet integrals and integral means within these classes.

## Contribution

It provides the first sufficient condition for univalence in a class of meromorphic functions with a pole and computes exact extremal values for associated Dirichlet integrals.

## Key findings

- Derived a sufficient univalence criterion for functions in the class (p).
- Computed the exact maximum of the Dirichlet integral elta(r,z/f) for univalent functions.
- Established sharp estimates for Dirichlet integrals and integral means in subclasses of (p).

## Abstract

Let $\mathcal{A}(p)$ be the class consisting of functions $f$ that are holomorphic in $\ID\setminus \{p\}$, $p\in (0,1)$ possessing a simple pole at the point $z=p$ with nonzero residue and normalized by the condition $f(0)=0=f'(0)-1$. In this article, we first prove a sufficient condition for univalency for functions in $\mathcal{A}(p)$. Thereafter, we consider the class denoted by $\Sigma(p)$ that consists of functions $f \in \mathcal{A}(p)$ that are univalent in $\ID$. We obtain the exact value for $\ds\max_ {f\in \Sigma(p)}\Delta(r,z/f)$, where the Dirichlet integral $\Delta(r,z/f)$ is given by $$ \Delta(r,z/f)=\ds\iint_{|z|<r} |\left(z/f(z)\right)'|^2 \,dx\, dy, \quad(z=x+iy),~0<r\leq 1. $$ We also obtain a sharp estimate for $\Delta(r,z/f)$ whenever $f$ belongs to certain subclasses of $\Sigma(p)$. Furthermore, we obtain sharp estimates of the integral means for the aforementioned classes of functions.