Research Article
Rational Fuzzy Cone Contractions on Fuzzy Cone Metric
Spaces with an Application to Fredholm Integral Equations
Saif Ur Rehman
1
and Hassen Aydi
2,3,4
1
Department of Mathematics, Gomal University, Dera Ismail Khan 29050, Pakistan
2
Institut Supérieur d’Informatique et des Techniques de Communication, Université de Sousse, H. Sousse, Tunisia
3
Department of Mathematics and Applied Mathematics, Sefako Makgatho Health Sciences University, Ga-Rankuwa, South Africa
4
China Medical University Hospital, China Medical University, Taichung, 40402, Taiwan
Correspondence should be addressed to Hassen Aydi; hassen.aydi@isima.rnu.tn
Received 28 February 2021; Accepted 22 April 2021; Published 10 May 2021
Academic Editor: Liliana Guran
Copyright © 2021 Saif Ur Rehman and Hassen Aydi. This is an open access article distributed under the Creative Commons
Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work
is properly cited.
This paper is aimed at proving some common fixed point theorems for mappings involving generalized rational-type fuzzy cone-
contraction conditions in fuzzy cone metric spaces. Some illustrative examples are presented to support our work. Moreover, as an
application, we ensure the existence of a common solution of the Fredholm integral equations: μðτÞ =
Ð
τ
0
Γðτ, v, μðvÞÞdv and νðτÞ
=
Ð
τ
0
Γðτ, v, νðvÞÞdv, for all μ ∈ U , v ∈ ½0, η, and 0< η ∈ ℝ, where U = Cð½0, η, ℝÞ is the space of all ℝ-valued continuous
functions on the interval ½0, η and Γ : ½0, η × ½0, η × ℝ ⟶ ℝ.
1. Introduction
In 1922, Banach [1] proved a “Banach contraction principle,”
which is stated as follows: “A self-mapping on a complete
metric space verifying the contraction condition has a unique
fixed point.” This principle plays a very important role in the
fixed point theory. A number of researches have generalized
it in many directions for single-valued and multivalued map-
pings in the context of metric spaces. Some of the findings
can be found in [2–13] and the references therein. Currently,
the fixed point theory is one of the most interested research
areas in the field of mathematics. In the last decades, it has
been investigated in many fields, such as game theory, graph
theory, economics, computer sciences, and engineering.
The theory of fuzzy sets was introduced by Zadeh [14],
while the concept of a fuzzy metric space (FM space) was
given by Kramosil and Michalek [15]. After that, the stronger
form of the metric fuzziness was presented by George and
Veeramani in [16]. Later on, in [17], Gregori and Sapena
proved some contractive-type fixed point results in complete
FM spaces. Some more fixed point results in FM spaces can
be found in [18–27] and the references therein.
Initially, in 2007, the concept of a cone metric space was
reintroduced by Huang and Zhang [28]. They proved some
nonlinear contractive-type fixed point results in cone metric
spaces. After the publication of this article, a number of
researchers have contributed their ideas in cone metric
spaces. Some of such works can be found in [29–34] and
the references therein.
In 2015, the basic concept of a fuzzy cone metric space
(FCM space) was given by Öner et al. [35]. They presented
some key attributes and a “fuzzy cone Banach contraction
theorem” in FCM spaces. Later, Rehman and Li [36]
extended and improved a “fuzzy cone Banach contraction
theorem” and proved some generalized fixed point theorems
in FCM spaces. Some more properties and related fixed point
results can be found in [37–47].
The aim of this research work is to establish some
rational-type fuzzy cone-contraction results in FCM spaces.
We use the concept of [36, 39] and prove some common
fixed theorems under generalized rational-type fuzzy cone-
contraction conditions in FCM spaces. Some illustrative
examples are presented. In the last section, we give an appli-
cation of two Fredholm integral equations (FIEs).
Hindawi
Journal of Function Spaces
Volume 2021, Article ID 5527864, 13 pages
https://doi.org/10.1155/2021/5527864