J. Nig. Soc. Phys. Sci. 4 (2022) 834 Journal of the Nigerian Society of Physical Sciences Collocation Approach for the Computational Solution Of Fredholm-Volterra Fractional Order of Integro-Differential Equations G. Ajileyea,∗, A.A. Jamesb, A. M. Ayindec, T. Oyedepod aDepartment of Mathematics and Statistics, Federal University Wukari, Taraba State, Nigeria. bDepartment of Mathematics, American University of Nigeria, Yola, Adamawa State, Nigeria. cDepartment of Mathematics, Moddibo-Adama University, Yola Nigeria. dFederal College of Dental Technology and Therapy, Enugu, Nigeria. Abstract In this work, a collocation technique is used to determine the computational solution to fractional order Fredholm-Volterra integro-differential equations with boundary conditions using Caputo sense. We obtained the linear integral form of the problem and transformed it into a system of linear algebraic equations using standard collocation points. The matrix inversion approach is adopted to solve the algebraic equation and substituted it into the approximate solution. We established the uniqueness and convergence of the method and some modelled numerical examples are provided to demonstrate the method’s correctness and efficiency. It is observed that the results obtained by our new method are accurate and performed better than the results obtained in the literature. The study will be useful to engineers and scientists. It is advantageous because it addresses the difficulty in tackling fractional order Fredholm-Volterra integro-differential problems using a simple collocation strategy. The approach has the advantage of being more accurate and reducing computer running time. DOI:10.46481/jnsps.2022.834 Keywords: Collocation, Fredholm-Volterra, Integro-differential, Fractional derivatives, Approximate Solution. Article History : Received: 27 May 2022 Received in revised form: 13 August 2022 Accepted for publication: 18 August 2022 Published: 03 October 2022 c© 2022 The Author(s). Published by the Nigerian Society of Physical Sciences under the terms of the Creative Commons Attribution 4.0 International license (https://creativecommons.org/licenses/by/4.0). Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Communicated by: J. Ndam 1. Introduction Fractional calculus is an aspect in mathematics that studies the properties of integrals combined with noninteger order derivatives.The concept and method of solving differential equations containing fractional derivatives of unknown functions are covered in this field (fractional differential ∗Corresponding author tel. no: +2348077092831 Email address: adewale.james@aun.edu.ng (G. Ajileye ) equations). Many prominent mathematicians, such as Liouville, Grunwald, Riemann, Euler, Langrange, Heaviside, Fourier, Abel, and others, established fractional calculus on a formal foundation[1]. Very recently, scholars developed huge interest in fractional calculus due to its relevance and application to many areas of scientific endeavors. Fractional differential equations, or those containing real and complex order derivatives have been more significant in describing the most broad fields of science and technology with peculiar dynamics of various processes involving complex systems [2]. 1 Ajileye et al. / J. Nig. Soc. Phys. Sci. 4 (2022) 834 2 Many different approaches have been adopted to investigate the solution of fractional integrodifferential equations, such as Adomian decompositions method [3-5], collocation method [6, 7], Laplace decomposition method [8, 9], Taylor expansion method [10], Least square method [9], differential transform method [11], homotopy perturbation method [12-18], sinc-collocation method [15-17] and variational iteration method [12, 13]. Linna et al. [20] considered a numerical method to solve fractional variational problem. They simplified the fractional variational problems by the operational matrices. The operational matrices are based on the Chelyshkov polynomials. The fractional variational problem was transformed into a set of algebraic equations. The unknown coefficients were solved using the Lagrange multiplier techniques. Avcı & Mahmudov [19] proposed a numerical method based on the fractional Taylor vector for solving multi-term fractional differential equations. The main idea of this method was to reduce the given problems to a set of algebraic equations by utilizing the fractional Taylor operational matrix of fractional integration. Some numerical examples were given to demonstrate the accuracy and applicability. The results show that the presented method was efficient and applicable. Fadugba [21] presented the Mellin transform for the solution of the fractional order equations. The Mellin transform approach occurs in many areas of applied mathematics and technology. The Mellin transform of fractional calculus of different flavours; namely the Riemann-Liouville fractionalderivative, Riemann-Liouville fractional integral, Caputo fractional derivative and the Miller-Ross sequential fractional derivative were obtained. In this study, we consider Fredholm-Volterra Integrodifferential equation of fractional order of the the form: D α xy(x) − P1y ′ (x) − P2y ′′ (x) − P0y(x) = g (x) + λ1 ∫ x 0 k1 (x, t) y (t) dt +λ2 ∫ 1 0 k2 (x, t) y (t) dt, (1) with the given boundary conditions y (a) = 0, y(b) = 0, a < x < b, (2) where y(x) is to be determined, Dαx is the Caputo’s derivative, k1 (x, t) and k2 (x, t) are the Fredholm and Volterra integral kanel function respectively. P j, Pα,λ j are known constants. g(x) is the known function 2. Basic Definitions Under this section, we present some definitions and basic concepts of fractional calculus for the formulation of the given problem Definition 2.1: The Caputo derivative with order α > 0 of the given function f (x), x ∈ (a, b) is defined as [ Litfi, Dehghan and Yousefi, 2011] C x D α a y(x) = 1 Γ(m −α) ∫ x a (x − s)m−α−1y(m)(s)d s, (3) where m − 1 ≤ α ≤ m, m ∈ N, x > 0 Definition 2.2: Let (an) , n ≥ 0 be a sequence of real numbers. The power series in x with coefficients an is an expression [ Edward, Ford and Simpson, 2002] y(x) = a0 + a1 x + a2 x 2 + a3 x 3 + · · ·aN x N = N∑ n=0 an x n = φ(x) A, (4) where φ(x) = [1 x x2 · · · xN ], A = [a0 a1 · · · aN ]T , then y(x, n) = xnA, n = 0(1)N, n ∈ Z+. Definition 2.3: Standard Collocation Method (SCM). This approach is used to find the collocation points that are desired within a certain interval. i.e [a,b] and is given by xi = a + (b − a)i N , i = 1, 2, 3, ...N. (5) Definition 2.4: A metric on a set M is a function d : M×M −→ R with the following properties. For all x, y ∈ M (a) d(x, y) ≥ 0; (b) d(x, y) = 0 ⇐⇒ x = y (c) d(x, y) = d(y, x) (d) d(x, y) ≤ d(x, z) + d(x, y) If d is a metric on M, then the pair (M, d) is called a metric space. Definition 2.5: Let (X, d) be a metric space, A mapping T : X −→ X is Lipschitzian if ∃ a constant L > 0 such that d(T x, T y) ≤ Ld(x, y) ∀ x, y ∈ X. Definition 2.6: Let y(x) be a continuous function, then 0 I β x ( C 0 D β xy(x) ) = y(x) − N∑ k=0 y(k)(0) k! xk, (6) where m − 1 < β < 1. Let p(s) be an integrable function, then 0 I β x ( p(s)) = 1 Γ(β) ∫ x 0 (x − s)β−1 p(s)d s. (7) 3. Mathematical Background In this section, combination of collocation method and power series approximation is employed for the computational solution of (FVID) of fractional order. Theorem 3.0: Banach’s fixed point theorem Let (X, d) be a complete metric space, then each contraction mapping T : X −→ X has a unique fixed point x of T in X, such that T (x) = x Lemma (3.1). Let y(x) be the solution to (1) subject to (2) , the integral form y (x) = W(x) + 1 Γ(α) ∫ x 0 (x − s)α−1 ( P2y ′′ (s) ) d s (8) 2 Ajileye et al. / J. Nig. Soc. Phys. Sci. 4 (2022) 834 3 + 1 Γ(α) ∫ x 0 (x − s)α−1 ( P1y ′ (s) ) d s + 1 Γ(α) ∫ x 0 (x − s)α−1 (P0y(s)) d s − 1 Γ(α) ∫ x 0 (x − s)α−1 [ λ1 ∫ s 0 k1 (s, t) y (t) dt + λ2 ∫ 1 0 k2 (s, t) y (t) dt ] where W(x) = N∑ k=0 y(k)(0) k! xk − 1 Γ(α) ∫ x 0 (x − s)α−1 g(s)d s. Multiply equation (1) by 0 I β x (.) gives 0 I α x (D αy(x)) = 0 I β x ( P2y ′′ (x) ) + 0 I β x ( P1y ′ (s) ) +0 I β x (P0y(s)) −0 I β x (g(x)) − 0 I β x [ λ1 ∫ s 0 k1 (s, t) y (t) dt + λ2 ∫ 1 0 k2 (s, t) y (t) dt ] . (9) Using(6) on equation (9)gives y(x) = N∑ k=0 y(k)(0) k! xk + 0 I β x ( P2y ′′ (x) ) + 0 I β x ( P1y ′ (s) ) +0 I β x (P0y(s)) (10) 0 I β x (g(x)) + 0 I β x (∫ b 0 k1(x, t)y(t)dt ) + 0 I β x (∫ s 0 k2(s, t)y(t)dt ) Applying equation (4) and (7) to (10) gives y(x) = N∑ k=0 y(k)(0) k! xk + 1 Γ(α) ∫ x 0 (x − s)α−1 P2 ( φ(s) ′′ ) d sA + 1 Γ(α) ∫ x 0 (x − s)α−1 P1 ( φ(s) ′ ) d sA + 1 Γ(α) ∫ x 0 (x − s)α−1 P0 (φ(s)) d sA − 1 Γ(α) ∫ x 0 (x − s)α−1 (g(s)) d s − 1 Γ(α) ∫ x 0 (x − s)α−1 [ λ1 ∫ s 0 k1 (s, t) φ(t) dt (11) +λ2 ∫ 1 0 k2 (s, t) φ(t) dt ] d sA . 3.1. Method of Solution Collocatiing at xi in equation (11) gives y(xi) = N∑ k=0 y(k)(0) k! xk + 1 Γ(α) ∫ xi 0 (xi − s) α−1 P2 ( φ(s) ′′ ) d sA + 1 Γ(α) ∫ xi 0 (xi − s) α−1 P1 ( φ(s) ′ ) d sA + 1 Γ(α) ∫ xi 0 (xi − s) α−1 P0 (φ(s)) d sA − 1 Γ(α) ∫ xi 0 (xi − s) α−1 (g(s)) d s − 1 Γ(α) ∫ xi 0 (xi − s) α−1 [ λ1 ∫ s 0 k1 (s, t) φ(t) dt (12) +λ2 ∫ 1 0 k2 (s, t) φ(t) dt ] d sA Applying (4) on (12) gives φ(xi)A = W(xi) +  1 Γ(α) ∫ xi 0 (xi − s) α−1 P2 ( φ(s) ′′ ) d s+ 1 Γ(α) ∫ xi 0 (xi − s) α−1 P1 ( φ(s) ′ ) d s+ 1 Γ(α) ∫ xi 0 (xi − s) α−1 P0 (φ(s)) d s − 1 Γ(α) ∫ xi 0 (xi − s) α−1 ( λ1 ∫ xi 0 k1 (xi, t) φ(t) dt +λ2 ∫ 1 0 k2 (xi, t) φ(t) dt ) d s  A, (13) where W(xi) = N∑ k=0 y(k)(0) k! xk − 1 Γ(α) ∫ xi 0 (xi − s) α−1 g(s)d s. Factorise the values of A from equation (13) gives W(xi) =  φ(xi) − 1 Γ(α) ∫ xi 0 (xi − s) α−1 P2 ( φ(s) ′′ ) d s− 1 Γ(α) ∫ xi 0 (xi − s) α−1 P1 ( φ(s) ′ ) d s− 1 Γ(α) ∫ xi 0 (xi − s) α−1 P0 (φ(s)) d s + 1 Γ(α) ∫ xi 0 (xi − s) α−1( λ1 ∫ s 0 k1 (s, t) φ(t) dt + λ2 ∫ 1 0 k2 (s, t) φ(t) dt ) d s  A. (14) Equation 14 can be in the form τn(xi)A =W(xi), (15) where τn(xi) =  φ(xi) − 1 Γ(α) ∫ xi 0 (xi − s) α−1 P2 ( φ(s) ′′ ) d s− 1 Γ(α) ∫ xi 0 (xi − s) α−1 P1 ( φ(s) ′ ) d s− 1 Γ(α) ∫ xi 0 (xi − s) α−1 P0 (φ(s)) d s + 1 Γ(α) ∫ xi 0 (xi − s) α−1( λ1 ∫ s 0 k1 (s, t) φ(t) dt + λ2 ∫ 1 0 k2 (s, t) φ(t) dt ) d s,  and A = [a0 a1 · · · aN ]T . Multiply both sides of equation(15) byτ−1n (xi) gives A =τ−1n (xi)W(xi). (16) Substituting A into the approximate solution (4) gives y(x) = φ(xi)τ −1 n (xi) W(xi) (17) 3 Ajileye et al. / J. Nig. Soc. Phys. Sci. 4 (2022) 834 4 4. Uniqueness of the Method In order to establish the uniqueness of the method, we introduce the following hypothesis H1 : k ∗ 1 = maxx∈[0,1] ∫ x 0 λ1 |k1(x, t)|dt H2 : k ∗ 2 = maxx∈[0,1] ∫ 1 0 λ2 |k2(x, t)|dt H3 : ∣∣∣y(m)1 − y(m)2 ∣∣∣ ≤ Lm |y1 − y2| . Lemma (4.1) (q-contraction) Let T : X −→ X be a mapping defined by theorem (3.0) for y1, y2 ∈ X. T is q-contraction if and only if  ∑2 n=0 Ln − ( k∗1 + k ∗ 2 ) Γ(α + 1)  < 1, then there exist a unique solution of T. (T y1) (x) = W(x) + 1 Γ(α) ∫ x 0 (x − s)α−1 ( P2y ′′ 1 (s) ) d s + 1 Γ(α) ∫ x 0 (x − s)α−1 ( P1y ′ 1(s) ) d s + 1 Γ(α) ∫ x 0 (x − s)α−1 (P0y1(s)) d s − 1 Γ(α) ∫ x 0 (x − s)α−1 [ λ1 ∫ s 0 k1 (s, t) y1 (t) dt +λ2 ∫ 1 0 k2 (s, t) y1 (t) dt ] d s and (T y2) (x) = W(x) + 1 Γ(α) ∫ x 0 (x − s)α−1 ( P2y ′′ 2 (s) ) d s + 1 Γ(α) ∫ x 0 (x − s)α−1 ( P1y ′ 2(s) ) d s + 1 Γ(α) ∫ x 0 (x − s)α−1 (P0y2(s)) d s − 1 Γ(α) ∫ x 0 (x − s)α−1 [ λ1 ∫ s 0 k1 (s, t) y2 (t) dt +λ2 ∫ 1 0 k2 (s, t) y2 (t) dt ] d s. Thus, |(T y1) (x) − (T y2) (x)| = 1 Γ(α) ∫ x 0 (x − s)α−1 P2 ∣∣∣y′′1 (s) − y′′2 (s)∣∣∣ d s + 1 Γ(α) ∫ x 0 (x − s)α−1 P1 ∣∣∣y′1(s) − y′2(s)∣∣∣ d s + 1 Γ(α) ∫ x 0 (x − s)α−1 P0 |y1(s) − y2(s)|d s − 1 Γ(α) ∫ x 0 (x − s)α−1  ∫ s 0 λ1 |k1(s, t)| |y1(t) − y2(t)|dt + ∫ 1 0 λ1 |k2(s, t)| |(y1(t) − y2(t))|dt  d s. Taking maximum of both sides and using H1 to H3 gives d (T y1(x), T y2(x)) ≤  L2 + L1 + L0 − ( k∗1 + k ∗ 2 ) Γ(α + 1)  d(y1, y2) Since T is a contraction ∑2 n=0 Ln − ( k∗1 + k ∗ 2 ) Γ(α + 1)  < 1. We can conclude that T has a unique solution. 5. Convergence Analysis We establish the convergence of the method yN (x) = W(x) + 1 Γ(α) ∫ x 0 (x − s)α−1 ( P2y ′′ N (s) ) d s + 1 Γ(α) ∫ x 0 (x − s)α−1 ( P1y ′ N (s) ) d s + 1 Γ(α) ∫ x 0 (x − s)α−1 (P0yN (s)) d s (18) − 1 Γ(α) ∫ x 0 (x − s)α−1 [ λ1 ∫ s 0 k1 (s, t) yN (t) dt +λ2 ∫ 1 0 k2 (s, t) yN (t) dt ] d s. Subtract (8) from (18) gives EN (x) = yN (x) − y(x). Hence |EN (x)| = 1 Γ(α) ∫ x 0 (x − s)α−1 |EN (s) (P2 + P1)|d s − 1 Γ(α) ∫ x 0 (x − s)α−1[ |λ1| ∣∣∣∣∣ ∫ s 0 k1 (s, t) EN (t)dt ∣∣∣∣∣ + |λ2| ∣∣∣∣∣∣ ∫ 1 0 k2 (s, t) EN (t)dt ∣∣∣∣∣∣d s. (20) Therefore ‖EN (x)‖∞ ‖EN (t)‖∞ ≤ 1 Γ(α) ∫ x 0 (x − s)α−1 ×  |En(s) (P2 + P1)| − 1 Γ(α) ∫ x 0 (x − s)α−1( |λ1| ∣∣∣∫ s 0 k1 (s, t) En(t)dt ∣∣∣ + |λ2| ∣∣∣∣∫ 10 k2 (s, t) En(t)dt∣∣∣∣  d s. The method converges 4 Ajileye et al. / J. Nig. Soc. Phys. Sci. 4 (2022) 834 5 6. Numerical Examples In this section, two numerical problems with boundary conditions are presented to text the efficiency and simplicity of the method. All computations are done with the aid of Maple 18. Let yn(x) and y(x) be the approximate and exact solution respectively. ErrorN = |yn(x) − y(x)| Example 1: Considering fractional integro-differential equation [17] y′′ (x) + 1 x D0.5x y(x) + 1 x2 y(x) = f (x) + ∫ x 0 sin (x − t) y(t)dt + ∫ 1 0 cos (x − t) y (t) dt, subject to the boundary conditions y(0) = 0, y(1) = 0, where f (x) = 5 + 1.50451x0.5 − 13x − 1.80541x1.5 −x2 + x3 − 2.067x cos(x) + 5.95385 sin(x). Exact solution y (x) = x2 (1 − x) Solution 1 We solve this problem at N = 3 and 5 but we use N = 3 for demonstration. Integral form of example 1 is y′′ (x) + 1 x ( 1 Γ(1 − 0.5) ∫ x 0 (x − t)−0.5 y(1)(t)dt ) + 1 x2 y(x) = f (x) + ∫ x 0 sin (x − t) y(t)dt + ∫ 1 0 cos (x − t) y (t) dt.(21) Using approximate solution (4) on (14) gives φ ′′ (x) + 1x ( 1 Γ(1−0.5) ∫ x 0 (x − t)−0.5 dd x (φ(t))dt ) + 1 x2 φ ′′ (x) − ∫ x 0 sin (x − t) φ(t)dt − ∫ 1 0 cos (x − t) φ (t) dt  A = f (x) (22) Equation (15) gives τ(x)A = f (x), (23) where τ(x) = φ ′′ (x) + 1x ( 1 Γ(1−0.5) ∫ x 0 (x − t)−0.5 dd x (φ(t))dt ) + 1x2 φ ′′ (x) − ∫ x 0 sin (x − t) φ(t)dt − ∫ 1 0 cos (x − t) φ (t) dt. Collocating at x3 = [ 1 3 2 3 1 ] and substituting the boundary conditions gives τ(x)∗A = f (x)∗, (24) where τi (x) =  8.1837497830 4.5298367530 3.5647166670 2.4321976680 1.0664602830 2.3357941530 3.8888778550 5.4288519160 -0.3011686789 1.5101524580 4.1068429140 8.5147669310 1 0 0 0 1 1 1 1  Table 1. Exact and approximate values, Example 1 x Exact N = 3 N = 5 0.2 0.032000000000 0.031999821270 0.031999851830 0.4 0.096000000000 0.095999891010 0.095999961860 0.6 0.144000000000 0.143999795600 0.143999892900 0.8 0.128000000000 0.127999546700 0.127999648400 1.0 0.000000000000 -8.444000000000e-7 -7.382000000000e-7 Table 2. Absolute Error for Example 1 x error3 error5 error [17]=32 0.2 -1.787300000000e-7 -1.481700000000e-7 2.048e-5 0.4 -1.089900000000e-7 -3.814000000000e-8 2.503e-5 0.6 -2.044000000000e-7 -1.071000000000e-8 1.789e-5 0.8 -1.071000000000e-7 -3.516000000000e-8 7.682e-6 1 -8.444000000000e-7 -7.382000000000e-8 3.034e-6 f (x) = [ 1.1325152410 -1.5399784720 -4.4079289640 0 0 ] . We now solve for the unknown values A (17) making use of matrix inversion results in; y3 = ( −4.2497275388 × 10−7 + 0.16917e − 5x+ 0.9999976497x2 − 0.9999997608x3 ) . Applying the same procedure for N = 5 gives y5 = ( −3.4773620430 × 10−7 + 8.9350760390 × 107 x + 1.0000017198x2 −1.0000070682x3 + 0.57092e − 5x4 − 0.16454e − 5x5 ) Example 2 Considering fractional integro-differential equation [17] y′′ (x)+ Dαx y(x) = f (x)+2 ∫ x 0 (x − t) y(t)dt + ∫ 1 0 ( x2 − t ) y (t) dt with the given boundary conditions y(0) = 0, y(1) = 0 where f (x) = − 1 30 − 6x + 181x2 20 + 4x3 − x5 10 + x6 15 and α = 1 Exact solution y (x) = x3 (x − 1) Solution 2 We solve this problem at N = 4 and 5, however, make use of N = 4 for demonstration. Integral form of example 2 is y′′ (x) + ( 1 Γ(2 − 1) ∫ x 0 (x − t)0 y(2)(t)dt ) (25) = f (x) + 2 ∫ x 0 (x − t) y(t)dt + ∫ 1 0 ( x2 − t ) y (t) dt 5 Ajileye et al. / J. Nig. Soc. Phys. Sci. 4 (2022) 834 6 Table 3. Exact and approximate values, Example 2 x Exact N = 4 N = 5 0.2 -0.6400000000e-2 -0.6400000000e-2 -0.6400000000e-2 0.4 -0.3840000000e-1 -0.3840000000e-1 -0.3840000000e-1 0.6 -0.864000000e-1 -0.8640000000e-1 -0.8640000000e-1 0.8 -0.1024000000 -0.1024000000 -0.1024000000 1.0 -0.9000000000e-3 -0.900000000e-3 -0.900000000e-3 Table 4. Absolute Error for Example 2 x error4 error5 error [17]=64 0.2 0.0 0.0 2.931e-7 0.4 0.0 0.0 3.915e-7 0.6 0.0 0.0 2.696e-7 0.8 0.0 0.0 1.011e-7 1 0.0 0.0 3.596e-8 Using approximate solution (4) on (18) gives φ′′(x) + ( 1 Γ(2−1) ∫ x 0 (x − t)0 d 2 d x2 (φ(t))dt ) −2 ∫ x 0 (x − t) φ(t)dt − ∫ 1 0 ( x2 − t ) φ (t) dt  A = f (x). (26) Equation (6.6) gives τ(x)A = f (x) (27) where τ(x) = φ ′′ (x) + ( 1 Γ(2−1) ∫ x 0 (x − t)0 d 2 d x2 (φ(t))dt ) −2 ∫ x 0 (x − t) φ(t)dt − ∫ 1 0 ( x2 − t ) φ (t) dt. Collocating at x4 = [ 0 14 2 4 3 4 1 ] and substituting the boundary conditions gives τ(x)∗A = f (x)∗ (28) where τi (x) =  1 2 0.3333333333 2.250000000 0.2000000000 0.1666666667 1 2 59 192 4193 1536 19169 10240 59393 61440 1 2 1 4 305 96 249 64 3473 960 1 2 37 192 1851 512 64211 10240 522457 61440 1 2 1 6 49 12 181 20 481 30 1 0 0 0 0 1 1 1 1 1  f (x) = [ - 130 - 55621 61440 - 131 480 137191 61440 419 60 0 0 ] We solve for the unknown values A using matrix inversion, results; y4 =  −2.2211399390 × 10−13 +3.0783153800 × 10−12 x −1.4125589590 × 10−11 x2 −1.0000000000x3 + 1.0000000000x4  Applying the same procedure for N = 5 gives y5 =  5.329070518000 × 10−15 +1.781685910000 × 10−12 x −1.580957587000 × 10−11 x2 −1.000000000000x3 +1.000000000000x4 +1.062971933000 × 10−11 x5  7. Conclusion Collocation approach is utilized to solving the fractional order Fredholm-Volterra integro-differential problems in this paper. The applied method is consistent, efficient and easy to compute. The results of the numerical example 1 as shown in table 1 shows that the approximate solution at N = 3 gives y3(x) = −4.2497275388 × 10−7 + 0.16917e − 5x + 0.9999976497x2 − 0.9999997608x3 and solving at N = 5 indicates that as the value of N increases, the error becomes smaller. We also compare our absolute errors with Alkan et al (2017) as shown in table 2, this clearly shows that our method performs better. The results of the numerical example 2 as shown in table 3 shows that the approximate solution obtained at N = 4 and 5 converges to the exact solution. Table 4 compares the errors in the method proposed by Alkan et al (2017) at N = 64 and errors in our new method which converges to the exact solution at N = 4. References [1] P. 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