Ostrowski type inequalities in the sense of generalized K -fractional integral operator for exponentially convex functions

: The investigation of the proposed methods is e ﬀ ective and convenient for solving the integrodi ﬀ erential and di ﬀ erence equations. In this note, we introduce the generalized K -fractional integral in terms of a new parameter K > 0 for exponentially convex functions. This paper o ﬀ ers some novel inequalities of Ostrowski-type using the generalized K -fractional integral. In the application viewpoint, we proved several corollaries that investigate for proving Hermite-Hadamard inequalities for generalized K -fractional integral operator. Some numerical examples are o ﬀ ered to explain the obtained results. Moreover, some applications of proposed results are presented to the demonstration of the e ﬃ ciency of the proposed technique. The numerical results show that our approach is superior to some related methodologies.


Introduction
There are numerous problems wherein fractional derivatives (non-integer order derivatives and integrals) attain a valuable position [4,5,8,16,24,27,31,36,41,60,62,63,70].It must be emphasized that fractional derivatives are furnished in many techniques, especially, characterizing three distinct approaches, which we are able to mention in an effort to grow the work in certainly one of them.Every classical fractional operator is typically described in terms of a particular significance.Many of the most well recognized definitions of fractional operators we can also point out the Riemann-Liouville, Caputo, Grunwald-Letnikov, and Hadamard operators [13], whose formulations include integrals with singular kernels and which may be used to have a check, as an example, issues involving the reminiscence effect [34].However, within the years 2010, specific formulations of fractional operators have seemed inside the literature [42].
On the other hand, there are numerous approaches to acquire a generalization of classical fractional integrals.Many authors introduce parameters in classical definitions or in some unique specific function [45], as we shall do below.Moreover, in a present paper, the authors introduce a parameter and enunciate a generalization for fractional integrals on a selected space, which they name generalized K-fractional integrals, and further advocate an Ostrowski type inequality modification of this generalization.A verity of such type of new definitions of fractional integrals and derivatives promotes future research to establish more new ideas and fractional integral inequalities by utilizing new fractional derivative and integral operators.Integral inequalities are used in countless mathematical problems such as approximation theory and spectral analysis, statistical analysis and the theory of distributions.Studies involving integral inequalities play an important role in several areas of science and engineering.In [53], the authors established certain Grüss type inequalities and some other inequalities containing generalized proportional fractional and generalized proportional fractional with respect to another function.Khan et al. [3] studied several inequalities for the conformable fractional integral operators.Nisar et al. [44] presented Gronwall inequalities involving the generalized Riemann-Liouville and Hadamard K-fractional derivatives with applications.In [39], Kwun et al. proved integrals associated with Ostrowski type inequalities and error bounds of Hadamard inequalities involving the generalized Riemann-Liouville K-fractional integral operators.Especially, several striking inequalities, properties, and applicability for the fractional integrals and derivatives are recently studied by various researchers.We refer the interesting readers to the works by [30,37,52,55].
In 1937, Ostrowski [46] established an interesting integral inequality associated with differentiable mappings in one dimension stipulates a bound between a function evaluated at an interior point z and the average of the function over an interval.That is The constant 1  4 is sharp in the sense that it cannot be replaced by a smaller one.We also observe that the tightest bound is obtained at z = ς 1 +ς 2 2 , resulting in the well-known mid-point inequality.Ostrowski inequalities have great importance while studying the error bounds of different numerical quadrature rules, for example, the midpoint rule, Simpson's rule, the trapezoidal rule, and other generalized K-fractional integrals, see [19,21].
Almost every mathematician knows the importance of convexity theory in every field of mathematics, for example in nonlinear programming and optimization theory.By using the concept of convexity, several integral inequalities have been introduced such as Jensen, Hermite-Hadamard and Slater inequalities, and so forth.Exponentially convex functions have emerged as a significant new class of convex functions, which have important applications in technology, data science, and statistics.The main motivation of this paper depends on new Ostrowski inequalities that have been proved via K-fractional integrals and applied for exponentially convex functions.Ostrowski inequality offers some new estimation of a function to its integral mean.It is beneficial in error estimations of quadrature rules in numerical analysis.Some particular cases have been discussed, which can be deduced from these consequences.
Recall the definition of an exponentially convex function, which is investigated by Dragomir and Gomm [20].
Exponentially convex function explored by Bernstein [14] in covariance formation then Avriel [11] established and investigated this concept by imposing the condition of r-convex functions.Dragomir and Gomm [20] proved the Hermite-Hadamard inequality by employing exponentially convex functions.Pal [47], Alirezai and Mathar [9] provided the fertile application of exponentially convex functions in information theory, optimization theory, and statistical theory.For observing various other kinds of exponentially convex functions and their generalizations, see [1,2,6,7,10,12,40,54,66,67].Due to its significance, Jakšetić and Pečarić [28] used another kind of exponentially convex function introduced in reference [14] and have provided some applications in Euler-Radau expansions and stolarsky means.Our intention is to use the exponentially convexity property of the functions as well as the absolute values of their derivatives in order to establish estimates for generalized K-fractional integrals.
Inspired by the above works, we give a novel approach for deriving new generalizations of Ostrowski type that correlates with exponentially convex functions and generalized K-fractional techniques in this paper.One highlight is that our consequences, which are more consistent and efficient, are accelerated via the fractional calculus technique.In addition, our consequences also taking into account the estimates for Hermite-Hadamard inequality for exponentially convex functions by employing Remark 2.1.We also investigate the applications of the two proposed methods to exponentially convex functions and fractional calculus.Furthermore, we give some numerical examples to illustrate the convergence efficiency of our theorems.The proposed numerical experiments show that our results are superior to some related results.

Preliminaries
In this section, we demonstrate some important concepts from fractional calculus that play a major role in proving the results of the present paper.The essential points of interest are exhibited in the monograph by Kilbas et al. [38].
In particular, we denote and Definition 2.2.( [32]) Let p ≥ 1 and Φ be an increasing and positive function on [0, ∞) We clearly see that . Now, we present a new fractional operator that is known as the generalized K-fractional integral operator of a function in the sense of another function Φ. Definition 2.3.Let ∈ χ q Φ (0, ∞) and Φ be an increasing positive function defined on [0, ∞) such that Φ (z) is continuous on [0, ∞) with Φ(0) = 0. Then the left and right generalized K-fractional integral operators of the function in the sense of the function Φ of order ρ > 0 are defined by respectively, where ρ ∈ C, (ρ) > 0 and Remark 2.1.From (2.1) and (2.2) we clearly see that (1) They turn into the both sided generalized RL-fractional integral operators [38] if K = 1.
(3) They lead to the both-sided RL-fractional integral operators if Φ(z) = z and K = 1.

Main results
In what follows, we assume that is a finite or infinite interval, is a positive integrable function defined on I and Φ is an increasing and positive function on (ς 1 , ς 2 ] such that Φ is continuous on (ς 1 , ς 2 ).Now, we are going to present several new Ostrowski-type inequalities for the exponentially convex functions via the generalized K-fractional integrals.
Proof.It follows from the monotonicity of Φ that From (3.2) and the hypothesis |(e (λ) ) | ≤ M we clearly see that After integrating above inequalities and then using Definition 2.3 we get (Φ(z) − Φ(ς 1 )) Inequalities (3.3) and (3.4) lead to the following modulus inequality Analogously, we have Making use of (3.6) and adopting the same procedure as we did for obtaining (3.5), we get the following modulus inequality Corollary 3.2.Let K = 1.Then Theorem 3.1 gives the Ostrowski-type inequality as follows Corollary 3.3.Letting Φ(z) = (z).Then Theorem 3.1 reduces to the following Ostrowski-type inequality for K-fractional integral Corollary 3.4.Let Φ(z) = (z) and K = 1.Then Theorem 3.1 leads to Corollary 3.5.Let Φ(z) = (z) and ρ = δ = K = 1.Then Theorem 3.1 becomes to the Ostrowski-type inequality In addition, we can get more results by use of Theorem 3.1 as follows.
Proof.It follows from the monotonicity of Φ that Inequality (3.20) and the hypothesis on (e ) lead to Integrating above inequalities and using the Definition 2.3 lead to ρ Again, making use of the fact the monotonicity of Φ we have Using (3.24) and adopting the same procedure as we did for obtaining (3.23), we get

Examples
The generalized K-fractional integral operator is very a useful operator in the theory of fractional calculus and its applications since it is already mentioned that it is eligible to use it as a solution of fractional order differential equations, integral equations and fractional Schrödinger equations.To show the accuracy of our results, we present two examples to support our obtained results in the previous section.
0 cos 2 λdλ ≈ 0.6427 and Adding the above equations, we get the left-hand side term of (3.1) as follows (Φ(z) − Φ(ς 1 )) On the other hand, we have and

Conclusion
In this paper, we proposed a novel technique with two different approaches for deriving several generalizations for an exponentially convex function that accelerates with generalized K-fractional integral operator.We also established strong convergence theorems for Ostrowski type inequalities via exponentially convex functions.By choosing different parameter values K and Φ, we analyzed the convergence behavior of our proposed methods in form of corollaries.Another aspect is that, to show the effectiveness of our novel generalizations, our results have potential applications in fractional integrodifferential, difference equations and fractional Schrödinger equations.Numerical examples show that our findings are consistent and efficient.Finally, we remark that the framework of the generalized K-fractional integral operator, it is of interest to further our results to the framework of Riemann-Liouville, Hadamard and conformable fractional integral operators.

. 25 )Remark 3 . 2 .
Therefore, inequality(3.19)follows easily from (3.23) and(3.25).From Theorem 3.4 we clearly see that (i) If K = 1, then we get the Ostrowski type inequality for the GRLF I. (ii) If Φ(z) = z, then we attain the Ostrowski type inequality for the K-fractional integral.(iii) If Φ(z) = z and K = 1, then we have the Ostrowski type inequality for the RLF I.