Generalized fractional integral inequalities for exponentially (s,m)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$(s,m)$\end{document}-convex functions

In this paper we have derived the fractional integral inequalities by defining exponentially (s,m)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$(s,m)$\end{document}-convex functions. These inequalities provide upper bounds, boundedness, continuity, and Hadamard type inequality for fractional integrals containing an extended Mittag-Leffler function. The results about fractional integral operators for s-convex, m-convex, (s,m)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$(s,m)$\end{document}-convex, exponentially convex, exponentially s-convex, and convex functions are direct consequences of presented results.


Introduction
Convex functions are very useful in mathematical analysis due to their fascinating properties and convenient characterizations.
Definition 1 A function f : I → R is said to be convex function if the following inequality holds: for all a, b ∈ I and t ∈ [0, 1]. If inequality (1.1) holds in reverse order, then the function f is called concave function.
A graphical interpretation of a convex function f over an interval [a, b] provides at a glance the following well-known Hadamard inequality: This inequality has been studied extensively, and a lot of its versions have been published by defining new functions obtained from inequality (1.1). Next we define some of these definitions. In [22], Toader gave the following definition of m-convex function. In [4], Awan et al. gave the following definition of exponentially convex function.
Definition 4 A function f : K → R, where K is an interval, is said to be an exponentially convex function if holds for all a, b ∈ K , t ∈ [0, 1], and α ∈ R. If the inequality in (1.3) is reversed, then f is called exponentially concave.
In [12], Mehreen and Anwar gave the following definition of exponentially s-convex function.
Definition 5 ([12]) Let s ∈ (0, 1] and K ⊆ [0, ∞) be an interval. A function f : K → R is said to be exponentially s-convex in the second sense if holds for all a, b ∈ K , t ∈ [0, 1], and α ∈ R. If the inequality in (1.4) is reversed, then f is called exponentially s-concave function.
The aim of this paper is to define a further generalization named exponentially (s, m)convex function (Definition 9) and explore the bounds of generalized fractional integral operators containing Mittag-Leffler functions in their kernels. The Mittag-Leffler function E σ (t) was introduced by Gosta [13] in 1903: where t, σ ∈ C, (σ ) > 0 and Γ (·) is the gamma function. The Mittag-Leffler function is a direct generalization of the exponential function to which it reduces for σ = 1. In the solution of fractional integral equations and fractional differential equations, the Mittag-Leffler function arises naturally. Due to its importance, the Mittag-Leffler function has been further generalized and extended by many researchers, we refer the reader to [3,9,19,20]. Recently in [2], Andrić et al. introduced a generalized Mittag-Leffler function defined as follows.
Remark 1 The function given in (1.5) is a generalization of the following Mittag-Leffler functions: (i) If p = 0 in (1.5), then it reduces to the Salim-Faraj function defined in [19].
(ii) If l = δ = 1 in (1.5), then it reduces to the function defined by Rahman et al. in [15].
Derivative property of the generalized Mittag-Leffler function is given in following lemma.
The Mittag-Leffler function is used to define generalized fractional integral operators. The left-sided and right-sided fractional integral operators containing Mittag-Leffler function (1.5) are defined as follows.
Then the generalized fractional integral operators containing Mittag-Leffler function are defined by is the Mittag-Leffler function given in (1.5).
Remark 2 Integral operators given in (1.7) and (1.8) are the generalization of the following fractional integral operators containing Mittag-Leffler function: (i) If we take p = 0, it reduces to the fractional integral operators defined by Salim and Faraj in [19]. (ii) If we take l = δ = 1, it reduces to the fractional integral operators defined by Rahman et al. in [15]. (iii) If we take p = 0 and l = δ = 1, it reduces to the fractional integral operators defined by Srivastava and Tomovski in [21]. (iv) If we take p = 0 and l = δ = k = 1, it reduces to the fractional integral operators defined by Prabhakar in [14]. (v) If we take p = ω = 0, it reduces to the right-sided and left-sided Riemann-Liouville fractional integrals.
We will follow the upcoming notations in the main results: In the upcoming section we define a new definition named exponentially (s, m)-convex function which generalizes convex, s-convex, m-convex, exponentially convex, and exponentially s-convex functions. Further this definition is used to establish the upper bounds of left-sided and right-sided generalized fractional integral operators (1.7) and (1.8). The upper bounds provide the continuity of these operators. A modulus inequality is obtained for differentiable functions which in absolute value are exponentially (s, m)-convex. Furthermore a fractional version of the Hadamard inequality is proved.

Main results
Then, for t ∈ [a, x) and σ ≥ 1, one can have the following inequality: As f is exponentially (s, m)-convex, therefore one can obtain By multiplying (2.2) and (2.3) and then integrating over [a, x], we get that is, the left integral operator satisfies the following inequality: (2.4) On the other hand, for t ∈ (x, b] and τ ≥ 1, one can have the following inequality: Again from exponential (s, m)-convexity of f , we have (2.6) By multiplying (2.5) and (2.6) and then integrating over that is, the right integral operator satisfies the following inequality: (2.7) By adding (2.4) and (2.7), the required inequality (2.1) can be obtained.
The following special cases are considered.

Corollary 1
If we set σ = τ in (2.1), then the following inequality is obtained:

Corollary 2 Along with the assumption of Theorem
, then the following inequality is obtained:
The next result provides the boundedness of a sum of left and right integrals at an arbitrary point for functions whose derivatives in absolute values are exponentially (s, m)convex.

Theorem 3 Let f : K ⊆ [0, ∞) − → R be a real-valued function. If f is differentiable and |f |
is exponentially (s, m)-convex, then for a, b ∈ K, a < b, and σ , τ ≥ 1, the following fractional integral inequality for generalized integral operators (1.7) and (1.8) holds: Proof Let x ∈ [a, b] and t ∈ [a, x), by using exponential (s, m)-convexity of |f |, we have (2.14) From (2.14), one can have (2.15) The product of (2.2) and (2.15) gives the following inequality: (2.16) After integrating the above inequality over [a, x], we get (2.17) The left-hand side of (2.17) is calculated as follows: Put xt = z, that is, t = xz, also using the derivative property (1.6) of Mittag-Leffler function, we have Now putting xz = t in the second term of the right-hand side of the above equation and then using (1.7), we get Therefore (2.17) takes the following form: (2.19) Also from (2.14) one can have (2.20) Following the same procedure as we did for (2.15), one can obtain (2.21) From (2.19) and (2.21), we get (2.22) Now we let x ∈ [a, b] and t ∈ (x, b]. Then, by exponential (s, m)-convexity of |f |, we have (2.23) On the same lines as we have done for (2.2), (2.15), and (2.20), one can get from (2.5) and (2.23) the following inequality: (2.24) From inequalities (2.22) and (2.24) via the triangular inequality, (2.13) can be obtained.

Corollary 5
If we put σ = τ in (2.13), then the following inequality is obtained: , α ∈ R. (2.26) It is required to give the following lemma which will be helpful to produce Hadamard type estimations for the generalized fractional integral operators.

Concluding remarks
This paper has investigated generalized fractional integral inequalities which provide the bounds of fractional integral operators containing Mittag-Leffler functions in their kernels. By setting different values of parameters involved in the Mittag-Leffler function, the results for various known fractional operators can be obtained. For example, by setting p = 0, fractional integral inequalities for fractional operators defined by Salim and Faraj in [19] can be obtained; by setting l = δ = 1, fractional integral inequalities for fractional operators defined by Rahman et al. in [15] can be deduced, by setting p = 0 and l = δ = 1, fractional integral inequalities for fractional operators defined by Shukla and Prajapati in [20] (see also [21]) can be deduced, by setting p = 0 and l = δ = k = 1, fractional integral inequalities for fractional operators defined by Prabhakar in [14] can be deduced, by setting p = ω = 0 fractional integral inequalities for Riemann-Liouville fractional integrals can be deduced. Also all the results of this paper hold for s-convex, m-convex, exponentially convex, exponentially s-convex, and convex functions. In particular results for (s, m)-convex functions, which are proved in [7], can be obtained.