• Journal of applied mathematics & informatics
• /
• v.39 no.3_4
• /
• pp.529-539
• /
• 2021

The purpose of this paper is to prove some fixed point theorems using (𝜓, 𝜑)-contractions via the concept of C-class functions in G_b-metric spaces. Moreover, an example is presented to illustrate the validity of our results.

• Journal of the Chungcheong Mathematical Society
• /
• v.32 no.1
• /
• pp.113-125
• /
• 2019

In this paper, I investigate the stability of the functional equation f(x + 2y) - 3f(x + y) + 3f(x) - f(x - y) - 3f(y) + 3f(-y) = 0 by using the fixed point theory in the sense of L. $C{\breve{a}}dariu$ and V. Radu.

• Korean Journal of Mathematics
• /
• v.26 no.4
• /
• pp.615-628
• /
• 2018

In this paper, we introduce the pioneering trigintic functional equation. Moreover, we establish the general solution of the trigintic functional equation and prove the Hyers-Ulam sum and product stabilities of the same equation in multi-Banach spaces by employing the fixed point approach.

• Journal of applied mathematics & informatics
• /
• v.37 no.5_6
• /
• pp.443-457
• /
• 2019

Some fixed point theorems and properties of diminishing orbital diameters for a few contractive mappings of integral type in complete metric spaces are proved. Four nontrivial examples are included.

• Korean Journal of Mathematics
• /
• v.27 no.2
• /
• pp.343-355
• /
• 2019

In this paper, we investigate the stability of the functional equation $$f(x+ky)-kf(x+y)+kf(x-y)-f(x-ky)-f(ky)+{\frac{k^3+k^2-2k}{2}}f(-y)-{\frac{k^3-k^2-2k}{2}}f(y)=0$$ by using the fixed point theory in the sense of L. $C{\breve{a}}dariu$ and V. Radu.

• Kyungpook Mathematical Journal
• /
• v.61 no.3
• /
• pp.613-629
• /
• 2021

In this paper, we present and prove new existence and uniqueness fixed point theorems for vector operators having a mixed monotone property in partially ordered product Banach spaces. Our results extend and improve existing works on τ-φ-concave operators in the scalar case. As an application, we study the existence and uniqueness of positive solutions for systems of nonlinear Neumann boundary value problems.

• Nonlinear Functional Analysis and Applications
• /
• v.26 no.2
• /
• pp.393-409
• /
• 2021

Three common fixed point theorems for weakly compatible mappings satisfying three classes of contractive inequalities of integral type are proved. Three examples are included. The results obtained in this paper extend and improve a few results existing in literature.

• Nonlinear Functional Analysis and Applications
• /
• v.26 no.3
• /
• pp.565-580
• /
• 2021

In this paper, first of all we prove a fixed point theorem for 𝜓_∫𝜑-weakly contractive mapping. Next, we prove some common fixed point theorems for a pair of weakly compatible self maps along with E.A. property and (CLR) property. An example is also given to support our results.

• Journal of applied mathematics & informatics
• /
• v.40 no.1_2
• /
• pp.259-266
• /
• 2022

The present investigation is concerned with certain subclasses of alpha-convex functions with fixed point and defined with subordination in the unit disc E = {z :| z |< 1}. The estimates of the first four coefficients for the functions in these classes are obtained. The results due to various authors follow as special cases.

• Korean Journal of Mathematics
• /
• v.30 no.1
• /
• pp.161-173
• /
• 2022

In this paper, we present a fixed point theorem for Meir-Keeler contraction in the framework of Rectangular M_b-metric Space. Our main result improves some existing results in literature. An example is also adopted to exhibit the utility of our main result.