Abstract
This paper extends the idea of subordination from the theory of fuzzy sets to the geometry theory of analytic functions with a single complex variable. The purpose of this work is to define fuzzy subordination and illustrate its main characteristics. New fuzzy differential subordinations will be introduced with the help of this effort. We define a linear operator using the concept of the -calculus operators. New fuzzy differential subordinations are created by employing the previously described operator, functions from the new class, and well-known lemmas. Specific corollaries derived from the operator proved the many examples created for the fuzzy differential subordinations, as well as the theorems, and demonstrate how the new theoretical conclusions apply to the fuzzy differential superordinations provided in this research.
Keywords:
analytic function; differential subordination; superordination; MSC:
30C45; 30C80
1. Introduction
To define fuzzy subordination, utilise the use of the fuzzy set notion initially presented by Zadeh in [1]. The fuzzy set idea that is a part of the differential subordination and superordination theories created in geometric function theory is used in this paper’s results. In geometric function theory, numerous mathematical domains have developed extensions as a result of the fuzzy set concept being used in investigations. The notion of a fuzzy set was used to investigate fuzzy subordination in geometric function theory in 2011 [2]. Since 2012 [3,4], when Miller and Mocanu’s classical theory of differential subordination [5] began to be modified by incorporating fuzzy theory elements, the theory of fuzzy differential subordination has been under development. The idea of fuzzy differential superordination was first presented in 2017 [6]. Several scholars have since examined various characteristics of differential operators, including fuzzy differential subordinations and superordinations [7,8,9,10,11,12,13].
This article presents the derivation of specific fuzzy differential subordinations and superordinations for an operator of the -Ruscheweyh operator and the -Cătas operator presented by Ali et al. in [14].
To derive the article’s findings, we employed the concepts and outcomes presented below:
Now suppose is the class of all analytic functions in the open unit disc . Also, represents ’s subclass, which includes provided by
we note that is the class of the function of the form
The class A, which is another well-known subclass of is made up of as shown by
with and
The subclass of is defined by
indicates the convex functions class in .
The following form applies to , where is donated by (1) and
The definition of convolution product is: *:
In particular ([15,16]) Jackson’s -difference operators are defined by
We might be able to use merely . It has already been written once
where
In [17], Aouf and Madian investigate the -analogue Cătas operator , as follows:
Also, the -Ruscheweyh operator was examined in 2014 by Aldweby and Darus [18]
where and are defined in (4).
We define
Now we define a new function as follows:
In [14], an extended multiplier operator was defined applying the operator as follows:
Definition 1
([14]). For and with the operator’s assistance we define the new linear extended multiplier by the -Ruscheweyh operator and the -Cătas operator, as:
For and (5), it is instead of
where
Differential subordinations and -calculus operators form the basis of several of the issues in geometric function theory. In 1990, Ismail et al. investigated the first applications of -analogue in geometric function theory by defining the class of -starlike functions [19]. A number of writers have concentrated on the -analogues of the Sălăgean differential operators defined in [20] and the Ruscheweyh differential operators created in [21]. The study of differential subordinations with a particular -Ruscheweyh-type derivative operator in [22] is one example.
2. Preliminaries
The below fundamentals will serve as a means of demonstrating the novel findings presented in the subsequent section.
Definition 2
([1]). A fuzzy set is pair , where ξ is a set, and a membership function.
Definition 3
([1]). A pair , where and is called a fuzzy subset of ξ and is said to be the membership function of the fuzzy set An application is called a fuzzy subset.
Definition 4
([23]). Suppose that ( is the positive real number and satisfies , defined as
and
It has been observed that corresponds to its fuzzy unit disk
Definition 5
([2]). Let and be a fuzzy subordinate to λ and written as or if every one of the following conditions is met and
Definition 6
([3]). Let and ζ be univalent in with Ω. If ω is analytic in with and satisfies the (second-order) fuzzy differential subordination,
i.e.,
then ω is a fuzzy dominant and fuzzy solution if
for all ω satisfying (7). A fuzzy dominant that satisfies
for all fuzzy dominant χ of (7) is fuzzy best dominant of (7).
Definition 7
([6]). Let and ζ be an analytic in . When the univalent function ω and verifies for any the fuzzy differential superordination:
then the fuzzy differential superordination has ω as a fuzzy solution. A fuzzy subordination of the fuzzy differential superordination χ an analytic function with
for all ω satisfying (8). A fuzzy subordinant that satisfies
for all fuzzy subordinant χ of (8) is fuzzy best subordinant of (8).
Assume that ℘ the set of analytic and injective functions on , with for and
Also, is the subclass of ℘ with
To derive these fuzzy inequalities, we require the lemmas listed below:
Lemma 1
([4]). Let λ be a convex function in and let the function
with n and If the function and
is analytic in , then
implies
and λ is fuzzy best -dominant.
Lemma 2
([4]). Let ζ be a convex with and set be a complex number with . If with and
is analytic in , then
implies
where
The function λ is convex and is the fuzzy best -dominant.
Lemma 3
([6]). Let ζ be a convex with and set with . When verifies for any the fuzzy differential superordination
and it is univalent in , then
is satisfied for any by the convex function where λ is the fuzzy best subordinant.
Lemma 4
([6]). Let a convex λ in and
with . If verifies for any the fuzzy differential superordination
and it is univalent in , then
is satisfied for any by the convex function which is the fuzzy best subordinant.
For i,u,e and e(e let
Lemma 5
([24]). For i,u and e(e, complex parameters
By using the operator we study the fuzzy differential subordination results in Section 3. Additionally, examples are given to illustrate possible applications of the findings. The best subordinants are also identified for fuzzy differential superordinations concerning the operator , which are examined in Section 4. Examples are also provided to highlight the significance of the findings.
3. Fuzzy Differential Subordination Results
We construct the class and establish the fuzzy differential subordination for the function that belongs to this class by utilising the operator .
Definition 8.
Let The class includes the function with
We see that for the class reduces to
Theorem 1.
Let λ be a convex function in , and and let
For consider
then
implies
λ is the fuzzy best dominant for
Proof.
We can write (11) as follows:
and differentiating it, we obtain
and
Differentiating the last relation, we obtain
Applying the final relation, the fuzzy differential subordination (12) will be
This means
the fuzzy differential subordination (13) have the next type:
Through Lemma 1, we find
then
where is the fuzzy best dominant. □
Theorem 2.
Proof.
Using the identical procedures as the Theorem 1, then
holds, with defined by (14).
Through Lemma 2, we find
similar to
where
By using Lemma 5, we find
Given that is a convex function and is symmetric around the real axis, we have
□
If we put in Theorem 2 we find
Corollary 1.
Let
then,
by using Lemma 5
Example 1.
If in Corollary 1, we find
then,
where
Theorem 3.
Let λ be convex with , we define
If verifies
then the fuzzy differential subordination
holds.
Proof.
Considering
clearly we will write
and differentiating it, we obtain
The fuzzy differential subordination (17) takes the form
Lemma 1 permits us to have then, (18) holds.
The reality that is the fuzzy best dominant. □
Theorem 4.
Assume that ζ is convex and , if verifies
then
for the convex function being the fuzzy best dominant.
Proof.
If we put in Theorem 5, we have
Corollary 2.
Considering ζ convex with , if verifies
then
where
is convex and it is the fuzzy best dominant.
Proof.
By Theorem 4 putting the fuzzy differential subordination (21) has the following shape:
Lemma 2, enables us to obtain
then
and
is the fuzzy best dominant. □
Example 2. From Corollary 2 if
we obtain
Let be convex in with and For and we obtain and and We conclude that Applying Theorem 4 yields
implies
Theorem 5.
Let λ be convex with ; we define If verifies
then
holds.
4. Fuzzy Differential Superordination Results
In this section, we provide the best subordinant for each fuzzy differential superordination that is being studied.
Theorem 6.
Assume that , ζ is convex in such that , and defined in (11). We let be a univalent in If
holds, then the fuzzy superordination
with the fuzzy best subordinant, which is convex.
Proof.
Differentiating (14), then can be stated as
which after differentiating it again, has the form
Using the final relation, (24) can be expressed the fuzzy differential superordination
Define
the fuzzy differential superordination (25), we obtain
Using Lemma 3, we deduce ; similarly,
by the fuzzy best subordinant convex function. □
Theorem 7.
Let , and where Suppose that is a univalent in and
then
is satisfied for the convex function as the fuzzy best subordinant.
Proof.
Assume that the fuzzy differential superordination (27) becomes
Through the use of Lemma 4, we obtain with
and
is convex and the fuzzy best subordinant. □
Example 3.
Let be convex in with and For and we obtain
and
We deduce Applying Theorem 7, we obtain
induce
Theorem 8.
Assume that and ζ be convex with . Considering is a univalent and if the fuzzy differential superordination
holds, then the fuzzy differential superordination
is satisfied for the convex function the fuzzy best subordinant.
Proof.
Denoting
We are able to write and differentiating it, we have
Using the form, the fuzzy differential superordination (28) becomes
By Lemma 3, we obtain
stated as
convex and the fuzzy best subordinant. □
Theorem 9.
Let with For , let be a univalent and If the fuzzy differential superordination
holds, then
is satisfied by the fuzzy best subordinant
convex function for
Proof.
At the presentation of the proof of Theorem 8 at the fuzzy superordination (29) assumes the shape
Using Lemma 3, we obtain by
is convex and the fuzzy best subordinant. □
Example 4.
Let be convex in with and . For and we obtain and univalent in and Since Applying Theorem 9, we deduce
implies
Theorem 10.
Let ζ be convex, with for and let be univalent in and If
holds, then
where the convex is the fuzzy best subordinant.
Proof.
Suppose
after differentiating it, we can write
in the form
In these conditions, the fuzzy differential superordination (30) becomes Utilising Lemma 3, we acquire , written as
with the convex , the fuzzy best subordinant. □
Theorem 11.
Assume that with At Assume that is univalent and If
holds, then
and the fuzzy best suordinant is the convex function
Proof.
By using the fuzzy differential superordination (31) takes the form
Utilising Lemma 3, we obtain with
and
is convex and the fuzzy best subordinant. □
5. Conclusions
The innovative findings demonstrated in this work, as stated in Definition 8, are associated with a new class of analytic functions presented in Definition 2. Applying the notion of the -difference operator, we build the -analogue multiplier-Ruscheweyh operator to introduce a subclass of univalent functions. These subclasses are then further investigated using techniques from fuzzy differential subordination theory in Section 3. In Section 4, we develop fuzzy differential fuzzy superordinations for the -analogue multiplier-Ruscheweyh operator .
The results discussed in this work further advance the topic of introducing and investigating new classes of analytic functions with the help of quantum calculus operators. Motivated by the encouraging outcomes of integrating components of quantum calculus into the research, we obtained some practical examples in Section 3 and Section 4.
Fuzzy differential subordinates are a powerful tool in mathematical analysis that allows us to extend the concept of derivatives to fuzzy functions. They have important applications in fields such as fuzzy control systems, where uncertainty and imprecision are prevalent. By incorporating fuzzy derivatives into our mathematical models, we can better understand and manipulate complex systems, leading to more effective and adaptive control strategies. Given that the second-order fuzzy differential subordinations found here could be extended to third-order fuzzy differential subordinations in light of the very recent findings by [25,26], the novel result in this paper will stimulate further research in the field of geometric function theory.
Author Contributions
Conceptualization, E.E.A. and R.M.E.-A.; methodology, E.E.A. and R.M.E.-A.; validation, E.E.A., R.M.E.-A. and A.M.A.; investigation, E.E.A. and R.M.E.-A.; writing—original draft preparation, E.E.A. and R.M.E.-A.; writing—review and editing, E.E.A., R.M.E.-A. and A.M.A.; supervision, E.E.A. and R.M.E.-A.; project administration, E.E.A. and R.M.E.-A. All authors have read and agreed to the published version of the manuscript.
Funding
This research received no external funding.
Data Availability Statement
Data are contained within the article.
Conflicts of Interest
The authors declare no conflicts of interest.
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