Wednesday, 11 May 2022

NUMERICAL SOLUTION OF NONLINEAR VOLTERRA-FREDHOLM INTEGRO-DIFFERENTIAL EQUATIONS VIA DIRECT METHOD USING TRIANGULAR FUNCTIONS

 Dr.K.R.Salini[1] and Dr.S.Bamini[2]

[1] Guest Lecturer, PG & Department of Mathematics, Government Arts & Science College, Kariyampatti, Tirupattur, Tamilnadu, India.

Email: shalinimanoj1985@gmail.com

[2] Research Coordinator, Assistant Professor, PG & Research Department of Mathematics, Marudhar Kesari Jain College For Women, Vaniyambadi, Tamilnadu, India.

Email: saransham07@gmail.com

Abstract

We determine the numerical solution of the specific nonlinear Voltera-Fredholm Integro-Differential Equation is proposed. The method is based on new vector forms for representation of triangular functions and its operational matrix.

Introduction

A set of basic functions and an appropriate projection method or a direct method. These methods often transform an integro-differential equation to a linear or nonlinear system of algebraic equations which can be solved by direct or iterative methods.

Consider a Volterra-Fredhlom Integro-differential equations of the form ๐‘ฅโ€ฒ(๐‘ )+๐‘ž(๐‘ )๐‘ฅ(๐‘ )+๐œ†1โˆซ๐‘˜1(๐‘ ,๐‘ก)๐น(๐‘ฅ(๐‘ก))๐‘‘๐‘ก10+๐œ†2โˆซ๐‘˜2(๐‘ ,๐‘ก)๐บ(๐‘ฅ(๐‘ก))๐‘‘๐‘ก10=๐‘ฆ(๐‘ )

๐‘ฅ(0)=๐‘ฅ0

Where the functions ๐น(๐‘ฅ(๐‘ก)) and ๐บ(๐‘ฅ(๐‘ก)) are polynomials of ๐‘ฅ(๐‘ก) with constant coefficients.

For convenience, we put ๐น(๐‘ฅ(๐‘ก))=[๐‘ฅ(๐‘ก)]๐‘›1 and ๐บ(๐‘ฅ(๐‘ก))=[๐‘ฅ(๐‘ก)]๐‘›2, where ๐‘›1 & ๐‘›2 are positive integers.

For ๐‘›1,๐‘›2=1, equation (1.1) is a linear integro- differential equation.

We present new vector forms of triangular functions (TFs), operational matrix of integration, expansion of functions of one and two variables with respect to TFs and other TFs properties.

By using new representations, a nonlinear integro-differential equation can be easily reduced to a nonlinear system of algebraic equations.

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Triangular Functions

Definition

Two ๐‘š-sets of triangular functions are defined over the intercal [0,๐‘ก) as ๐‘‡1๐‘–(๐‘ก)={1โˆ’๐‘กโˆ’๐‘–โ„Žโ„Ž๐‘–โ„Žโ‰ค๐‘ก<(๐‘–+1)โ„Ž0๐‘œ๐‘กโ„Ž๐‘’๐‘Ÿ๐‘ค๐‘–๐‘ ๐‘’ ๐‘‡2๐‘–(๐‘ก)={๐‘กโˆ’๐‘–โ„Žโ„Ž๐‘–โ„Žโ‰ค๐‘ก<(๐‘–+1)โ„Ž0๐‘œ๐‘กโ„Ž๐‘’๐‘Ÿ๐‘ค๐‘–๐‘ ๐‘’

Where ๐‘–=0,1,2โ€ฆ๐‘šโˆ’1 with a positive integer value for m.

Also consider โ„Ž=๐‘‡/๐‘š, and ๐‘‡1๐‘– as the ๐‘–๐‘กโ„Ž left-handed triangular function and ๐‘‡2๐‘– as

the ๐‘–๐‘กโ„Ž right-handed triangular function.

It is assumed that ๐‘‡=1, so TFs are defined over [0,1) and โ„Ž=1/๐‘š.

From the definition of TFs, it is clear that triangular functions are disjoint, orthogonal

and complete.

We can write โˆซ๐‘‡1๐‘–10(๐‘ก)๐‘‡1๐‘—(๐‘ก)๐‘‘๐‘ก=โˆซ๐‘‡2๐‘–10(๐‘ก)๐‘‡2๐‘—(๐‘ก)๐‘‘๐‘ก={โ„Ž3๐‘–=๐‘—0๐‘–โ‰ ๐‘—

Also, โˆ…๐‘–(๐‘ก)=๐‘‡1๐‘–(๐‘ก)+๐‘‡2๐‘–,๐‘–=0,1,โ€ฆ๐‘šโˆ’1

Where โˆ…๐‘–(๐‘ก) is the ๐‘–th block-pulse function defined as โˆ…๐‘–(๐‘ก)={1๐‘–โ„Žโ‰ค๐‘ก<(๐‘–+1)โ„Ž0๐‘œ๐‘กโ„Ž๐‘’๐‘Ÿ๐‘ค๐‘–๐‘ ๐‘’

Where ๐‘–=0,1,โ€ฆ๐‘šโˆ’1.

Vector Forms

Consider the first ๐‘š terms of the left-handed triangular functions and the first ๐‘š terms of the right- handed triangular functions and write them concisely as ๐‘š-vectors. ๐‘‡1(๐‘ก)=[๐‘‡10(๐‘ก),๐‘‡11(๐‘ก),โ€ฆ๐‘‡1๐‘šโˆ’1(๐‘ก)]๐‘‡

๐‘‡2(๐‘ก)=[๐‘‡20(๐‘ก),๐‘‡21(๐‘ก),โ€ฆ๐‘‡2๐‘šโˆ’1(๐‘ก)]๐‘‡

Where ๐‘‡1(๐‘ก) and ๐‘‡2(๐‘ก) are called left-handed triangular functions (LHTF) and right-handed triangular functions (RHTF) vector, respectively.

The product of two TFs vectors are

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๐‘‡1(๐‘ก)๐‘‡1๐‘‡(๐‘ก)โ‰…( ๐‘‡10(๐‘ก)0โ‹ฏโ‹ฏโ‹ฏ00๐‘‡11(๐‘ก)โ‹ฏโ‹ฏโ‹ฏ0โ‹ฎโ‹ฎ0โ‹ฎโ‹ฎ0โ‹ฎโ‹ฎโ‹ฏโ‹ฎโ‹ฎโ‹ฏโ‹ฎโ‹ฎโ‹ฏโ‹ฎโ‹ฎ๐‘‡1๐‘šโˆ’1(๐‘ก))

๐‘‡2(๐‘ก)๐‘‡2๐‘‡(๐‘ก)โ‰…( ๐‘‡20(๐‘ก)0โ‹ฏโ‹ฏโ‹ฏ00๐‘‡21(๐‘ก)โ‹ฏโ‹ฏโ‹ฏ0โ‹ฎโ‹ฎ0โ‹ฎโ‹ฎ0โ‹ฎโ‹ฎโ‹ฏโ‹ฎโ‹ฎโ‹ฏโ‹ฎโ‹ฎโ‹ฏโ‹ฎโ‹ฎ๐‘‡2๐‘šโˆ’1(๐‘ก)) ๐‘‡1(๐‘ก)๐‘‡2๐‘‡(๐‘ก)=0

๐‘‡2(๐‘ก)๐‘‡1๐‘‡(๐‘ก)=0

Where 0 is the ๐‘ง๐‘’๐‘Ÿ๐‘œ ๐‘šร—๐‘š matrix.

Also โˆซ๐‘‡110(๐‘ก)๐‘‡1๐‘‡(๐‘ก)๐‘‘๐‘ก=โˆซ๐‘‡2(๐‘ก)๐‘‡1๐‘‡(๐‘ก)๐‘‘๐‘ก10โ‰…โ„Ž3๐ผ

โˆซ๐‘‡110(๐‘ก)๐‘‡2๐‘‡(๐‘ก)๐‘‘๐‘ก=โˆซ๐‘‡2(๐‘ก)๐‘‡1๐‘‡(๐‘ก)๐‘‘๐‘ก10โ‰…โ„Ž6๐ผ

In which ๐ผ is an ๐‘šร—๐‘š identity matrix.

TFs Expansion

The expansion of a function ๐‘“(๐‘ก) over [0,1) with respect to TFs written as ๐‘“(๐‘ก)โ‰…ฮฃ๐‘๐‘–๐‘šโˆ’1๐‘–=0๐‘‡1๐‘–(๐‘ก)+ฮฃ๐‘‘๐‘–๐‘šโˆ’1๐‘–=0๐‘‡2๐‘–(๐‘ก) ๐‘“(๐‘ก)=๐‘๐‘‡๐‘‡1(๐‘ก)+๐‘‘๐‘‡๐‘‡2(๐‘ก)

Where we may put ๐‘๐‘–=๐‘“(๐‘–โ„Ž) and ๐‘‘๐‘–=๐‘“((๐‘–+๐‘–)โ„Ž) for ๐‘–=0,1,2,..๐‘šโˆ’1.

Operational Matrix of Integration

Expressing โˆซ๐‘‡1(๐œ)๐‘‘๐œโ‰…๐‘ƒ1๐‘‡1(๐‘ )+๐‘ƒ2๐‘‡2(๐‘ )๐‘ 0

โˆซ๐‘‡2(๐œ)๐‘‘๐œโ‰…๐‘ƒ1๐‘‡1(๐‘ )+๐‘ƒ2๐‘‡2(๐‘ )๐‘ 0

Where ๐‘ƒ1๐‘šร—๐‘š and ๐‘ƒ2๐‘šร—๐‘š are called operational matrices of integration in TFs domain and represented as follows ๐‘ƒ1=โ„Ž2( 011โ‹ฏ1001โ‹ฏ10โ‹ฎ00โ‹ฎ00โ‹ฎ0โ‹ฏโ‹ฑโ‹ฏ1โ‹ฎ0)

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๐‘ƒ2=โ„Ž2( 111โ‹ฏ1011โ‹ฏ10โ‹ฎ00โ‹ฎ00โ‹ฎ0โ‹ฏโ‹ฑโ‹ฏ1โ‹ฎ1)

So the integral of any function ๐‘“(๐‘ก) can be approximated as โˆซ๐‘“(๐œ)๐‘‘๐œโ‰…๐‘๐‘‡๐‘‡1(๐‘ )+๐‘‘๐‘‡๐‘‡2(๐‘ )๐‘‘๐œ๐‘ 0 โˆซ๐‘“(๐œ)๐‘‘๐œโ‰…(๐‘+๐‘‘)๐‘‡๐‘ƒ1๐‘‡1(๐‘ )+(๐‘+๐‘‘)๐‘‡๐‘ƒ2๐‘‡2(๐‘ )๐‘ 0

New Representation of TFs Vector Forms and Other Properties

We define a new representation of TFs vector forms. Then, some characteristics of TFs are presented using the new definition.

Definition and Expansion

Let ๐‘‡(๐‘ก) be a 2๐‘š-vector defined as ๐‘‡(๐‘ก)=(๐‘‡1(๐‘ก)๐‘‡2(๐‘ก)),0<๐‘ก<1

Where ๐‘‡1(๐‘ก) and ๐‘‡2(๐‘ก) have been defined in (1.2).

Now, the expansion of ๐‘“(๐‘ก) with respect to TFs can be written as ๐‘“(๐‘ก)โ‰…๐น1๐‘‡๐‘‡1(๐‘ก)+๐น2๐‘‡๐‘‡2(๐‘ก)

โ‰…๐น๐‘‡๐‘‡(๐‘ก)

Where ๐น1 &๐น2 are TFs co-efficients with

๐น1๐‘–=๐‘“(๐‘–โ„Ž)& ๐น2๐‘–=๐‘“((๐‘–+1)โ„Ž),

For ๐‘–=0,1,โ€ฆ๐‘šโˆ’1.

Also, 2๐‘š-vector ๐น is defined as ๐น=(๐น1๐น2)

Now, assume that ๐‘˜(๐‘ ,๐‘ก) is a function of two variables. It can be expanded with respect to TFs as follows

๐‘˜(๐‘ ,๐‘ก)โ‰…๐‘‡๐‘‡(๐‘ )๐พ๐‘‡(๐‘ก)

Where ๐‘‡(๐‘ )& ๐‘‡(๐‘ก) are 2๐‘š1&2๐‘š2 dimensional triangular functions and ๐พ is a

2๐‘š1ร—2๐‘š2 TFs coefficient matrix.

For convenience, we put ๐‘š1=๐‘š2=๐‘š. So matrix ๐พ can be written as

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๐พ=((๐พ11)๐‘šร—๐‘š(๐พ12)๐‘šร—๐‘š(๐พ21)๐‘šร—๐‘š(๐พ22)๐‘šร—๐‘š)

Where ๐พ11,๐พ12,๐พ21,๐พ22 can be compted by sampling the function ๐‘˜(๐‘ ,๐‘ก) at points ๐‘ ๐‘– & ๐‘ก๐‘— such that ๐‘ ๐‘–=๐‘–โ„Ž & ๐‘ก๐‘—=๐‘—โ„Ž, for ๐‘–,๐‘—=0,1,โ€ฆ๐‘š. (๐พ11)๐‘–๐‘—=๐‘˜(๐‘ ๐‘–,๐‘ก๐‘—),๐‘–=0,1,โ€ฆ๐‘šโˆ’1,๐‘—=0,1,โ€ฆ๐‘šโˆ’1 (๐พ12)๐‘–๐‘—=๐‘˜(๐‘ ๐‘–,๐‘ก๐‘—),๐‘–=0,1,โ€ฆ๐‘šโˆ’1,๐‘—=0,1,โ€ฆ๐‘š (๐พ21)๐‘–๐‘—=๐‘˜(๐‘ ๐‘–,๐‘ก๐‘—),๐‘–=0,1,โ€ฆ๐‘š,๐‘—=0,1,โ€ฆ๐‘šโˆ’1 (๐พ22)๐‘–๐‘—=๐‘˜(๐‘ ๐‘–,๐‘ก๐‘—),๐‘–=0,1,โ€ฆ๐‘š,๐‘—=0,1,โ€ฆ๐‘š

Product Properties

Let ๐‘‹ be an 2๐‘š-vertor which can be written as ๐‘‹๐‘‡=(๐‘‹1๐‘‡ ๐‘‹2๐‘‡) such that ๐‘‹1 & ๐‘‹2 are ๐‘š-vectors.

It can be concluded from (1.3) & (1.4) that ๐‘‡(๐‘ก)๐‘‡๐‘‡(๐‘ก)๐‘‹=(๐‘‡1(๐‘ก)๐‘‡2(๐‘ก))(๐‘‡๐‘‡(๐‘ก)๐‘‡2๐‘‡(๐‘ก))(๐‘‹1๐‘‹2)

โ‰…(๐‘‘๐‘–๐‘”(๐‘‡1(๐‘ก))๐‘œ๐‘šร—๐‘š๐‘œ๐‘šร—๐‘š๐‘‘๐‘–๐‘”(๐‘‡2(๐‘ก)))(๐‘‹1๐‘‹2)

=๐‘‘๐‘–๐‘” (๐‘‡(๐‘ก))๐‘‹

=๐‘‘๐‘–๐‘”(๐‘‹)๐‘‡(๐‘ก)

Therefore,

๐‘‡(๐‘ก)๐‘‡๐‘‡(๐‘ก)๐‘‹โ‰…๐‘‹ฬ… ๐‘‡(๐‘ก)

Where ๐‘‹ฬ…=๐‘‘๐‘–๐‘”(๐‘‹) is an 2๐‘šร—2๐‘š diagonal matrix.

Let ๐ต be a 2๐‘šร—2๐‘š matrix as ๐ต=((๐ต11)๐‘šร—๐‘š(๐ต12)๐‘šร—๐‘š(๐ต21)๐‘šร—๐‘š(๐ต22)๐‘šร—๐‘š)

So, it can be similarly concluded from equations (1.3) and (1.4) that ๐‘‡(๐‘ก)๐ต๐‘‡(๐‘ก)=๐‘‡1๐‘‡(๐‘ก)๐‘‡2๐‘‡(๐‘ก)(๐ต11๐ต12๐ต21๐ต22)(๐‘‡1(๐‘ก)๐‘‡2(๐‘ก)) โ‰…๐‘‡1๐‘‡(๐‘ก)๐ต11๐‘‡1(๐‘ก)+๐‘‡2๐‘‡(๐‘ก)๐ต22๐‘‡2(๐‘ก) โ‰…๐ตฬ‚11๐‘‡๐‘‡1(๐‘ก)+๐ตฬ‚22๐‘‡๐‘‡2(๐‘ก)

Where ๐ตฬ‚11 and ๐ตฬ‚22 are ๐‘šโˆ’vectors with elements equal to the diagonal entries of matrices ๐ต11 and ๐ต22 respectively.

Therefore,

๐‘‡๐‘‡(๐‘ก)๐ต๐‘‡(๐‘ก)โ‰…๐ตฬ‚ ๐‘‡๐‘‡(๐‘ก)

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In which ๐ตฬ‚ is a 2๐‘š- vector with elements equal to the diagonal entries of matrix ๐ต.

It is immediately concluded from equation (1.5) that โˆซ๐‘‡10(๐‘ก)๐‘‡๐‘‡(๐‘ก)๐‘‘๐‘ก=โˆซ(๐‘‡1(๐‘ก)๐‘‡2(๐‘ก))๐‘‡1๐‘‡(๐‘ก)๐‘‡2๐‘‡(๐‘ก)๐‘‘๐‘ก10

=โˆซ(๐‘‡1(๐‘ก)๐‘‡1๐‘‡(๐‘ก)๐‘‡1(๐‘ก)๐‘‡2๐‘‡(๐‘ก)๐‘‡2(๐‘ก)๐‘‡1๐‘‡(๐‘ก)๐‘‡2(๐‘ก)๐‘‡2๐‘‡(๐‘ก))๐‘‘๐‘ก10

โ‰…(โ„Ž3๐ผ๐‘šร—๐‘šโ„Ž6๐ผ๐‘šร—๐‘šโ„Ž6๐ผ๐‘šร—๐‘šโ„Ž3๐ผ๐‘šร—๐‘š)

Therefore,

โˆซ๐‘‡10(๐‘ก)๐‘‡๐‘‡(๐‘ก)๐‘‘๐‘กโ‰…๐ท

Where ๐ท is the following 2๐‘šร—2๐‘š matrix. ๐ท=โ„Ž3( 10โ‹ฏ012โ„0โ‹ฏ001โ‹ฏ0012โ„โ‹ฏ0โ‹ฎ012โ„0โ‹ฎ0โ‹ฎ0012โ„โ‹ฎ0โ‹ฑโ‹ฏโ‹ฏโ‹ฏโ‹ฑโ‹ฏโ‹ฎ100โ‹ฎ12โ„โ‹ฎ010โ‹ฎ0โ‹ฎ001โ‹ฎ0โ‹ฑโ€ฆโ‹ฏโ‹ฏโ‹ฑโ‹ฏโ‹ฎ12โ„00โ‹ฎ1)

Operational Matrix

Expressing โˆซ๐‘‡(๐œ)๐‘‘๐œ๐‘ 0 in terms of ๐‘‡(๐‘ ), we can write โˆซ๐‘‡(๐œ)๐‘‘๐œ๐‘ 0=โˆซ(๐‘‡1(๐œ)๐‘‡2(๐œ))๐‘‘๐œ๐‘ 0

โ‰…(๐‘ƒ1๐‘‡1(๐‘ )+๐‘ƒ2๐‘‡2(๐‘ )๐‘ƒ1๐‘‡1(๐‘ )+๐‘ƒ2๐‘‡2(๐‘ ))

=(๐‘ƒ1๐‘ƒ2๐‘ƒ1๐‘ƒ2)(๐‘‡1(๐‘ )๐‘‡2(๐‘ ))

So, โˆซ๐‘‡(๐œ)๐‘‘๐œ๐‘ 0โ‰…๐‘ƒ๐‘‡(๐‘ )

Where ๐‘ƒ2๐‘šร—2๐‘š, operational matrix of ๐‘‡(๐‘ ) is

๐‘ƒ=(๐‘ƒ1๐‘ƒ2๐‘ƒ1๐‘ƒ2) (

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Where ๐‘ƒ1 & ๐‘ƒ2 are given by

The integral of any function ๐‘“(๐‘ก) can be approximated as โˆซ๐‘“(๐œ)๐‘‘๐œ๐‘ 0โ‰…โˆซ๐น๐‘‡๐‘‡(๐œ)๐‘‘๐œ๐‘ 0

โ‰…๐น๐‘‡๐‘ƒ๐‘‡(๐‘ )

Solving Nonlinear Integro-Differential Equation

Consider the following nonlinear Volterra-Fredhlom integro-differential equation

{๐‘ฅโ€ฒ(๐‘ )+๐‘ž(๐‘ )๐‘ฅ(๐‘ )+๐œ†1โˆซ๐‘˜1(๐‘ ,๐‘ก)[๐‘ฅ(๐‘ก)]๐‘›1๐‘‘๐‘ก+๐‘ 0๐œ†2โˆซ๐‘˜2(๐‘ ,๐‘ก)[๐‘ฅ(๐‘ก)]๐‘›2๐‘‘๐‘ก=๐‘ฆ(๐‘ )๐‘ 0๐‘ฅ(0)=๐‘ฅ0, 0โ‰ค๐‘ <1,๐‘›1,๐‘›2โ‰ฅ1

Where the parameters ๐œ†1 and ๐œ†2 and โ„’2 functions ๐‘ž(๐‘ ),๐‘ฆ(๐‘ ),๐‘˜1(๐‘ ,๐‘ก),๐‘˜2(๐‘ ,๐‘ก) are known but ๐‘ฅ(๐‘ ) is not.

The appearance of initial condition equation. This is necessary to ensure the existence of a solution.

Approximating functions

๐‘ฅ(๐‘ ),๐‘ฅโ€ฒ(๐‘ ),๐‘ž(๐‘ ),๐‘ฆ(๐‘ ),[๐‘ฅ(๐‘ก)]๐‘›1,[๐‘ฅ(๐‘ก)]๐‘›2,๐‘˜1(๐‘ ,๐‘ก),๐‘˜2(๐‘ ,๐‘ก)

with respect to TFs, ๐‘ฅ(๐‘ )โ‰…๐‘ฅ๐‘‡(๐‘ )๐‘‹ ๐‘ฅโ€ฒ(๐‘ )โ‰…๐‘‹โ€ฒ๐‘‡๐‘‡(๐‘ )=๐‘‡๐‘‡๐‘‹โ€ฒ

๐‘ž(๐‘ )โ‰… ๐‘„๐‘‡๐‘‡(๐‘ )=๐‘‡๐‘‡(๐‘ )๐‘„

๐‘ฆ(๐‘ )โ‰… ๐‘Œ๐‘‡๐‘‡(๐‘ )=๐‘‡๐‘‡(๐‘ )๐‘Œ [๐‘ฅ(๐‘ก)]๐‘›1โ‰…๐‘‹๐‘›1๐‘‡๐‘‡(๐‘ )=๐‘‡๐‘‡(๐‘ )๐‘‹๐‘›1 [๐‘ฅ(๐‘ก)]๐‘›2โ‰…๐‘‹๐‘›2๐‘‡๐‘‡(๐‘ )=๐‘‡๐‘‡(๐‘ )๐‘‹๐‘›2 ๐‘˜1(๐‘ ,๐‘ก)โ‰…๐‘‡๐‘‡๐พ1๐‘‡(๐‘ก)

๐‘˜2(๐‘ ,๐‘ก)โ‰…๐‘‡๐‘‡๐พ2๐‘‡(๐‘ก)

Where 2๐‘š-vectors ๐‘‹,๐‘‹โ€ฒ,๐‘„,๐‘Œ,๐‘‹๐‘›1,๐‘‹๐‘›2 and 2๐‘šร—2๐‘š matrices ๐พ1 & ๐พ2 are TFs coefficients of

๐‘ฅ(๐‘ ),๐‘ฅโ€ฒ(๐‘ ),๐‘ž(๐‘ ),๐‘ฆ(๐‘ ),[๐‘ฅ(๐‘ก)]๐‘›1,[๐‘ฅ(๐‘ก)]๐‘›2,๐‘˜1(๐‘ ,๐‘ก),๐‘˜2(๐‘ ,๐‘ก) respectively.

Lemma

Let 2๐‘š-vectors ๐‘‹ and ๐‘‹๐‘› be TFs coefficients of ๐‘ฅ(๐‘ ) and [๐‘ฅ(๐‘ )]๐‘› respectively. If

๐‘‹=(๐‘‹1๐‘‡๐‘‹2๐‘‡)๐‘‡=(๐‘‹10,๐‘‹11,โ€ฆ,๐‘‹1๐‘šโˆ’1,๐‘‹20,๐‘‹21โ€ฆ๐‘‹2๐‘šโˆ’1)๐‘‡, then

๐‘‹๐‘›=(๐‘‹10,๐‘‹11,โ€ฆ,๐‘‹1๐‘šโˆ’1,๐‘‹20,๐‘‹21โ€ฆ๐‘‹2๐‘šโˆ’1)๐‘‡

Where ๐‘›โ‰ฅ1 is a positive integer.

Proof:

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When ๐‘›=1, , follows at once from [๐‘ฅ(๐‘ )]๐‘›=๐‘ฅ(๐‘ ).

Suppose that (4.16), holds for ๐‘›, we shall deduce it for ๐‘›+1.

Since [๐‘ฅ(๐‘ )]๐‘›+1โ‰…(๐‘‹๐‘‡๐‘‡(๐‘ )).(๐‘‹1๐‘‡๐‘‡(๐‘ ))

=๐‘‹๐‘‡๐‘‡(๐‘ )๐‘‡๐‘‡(๐‘ )๐‘‹๐‘› =๐‘‹๐‘‡๐‘‹๐‘›ฬƒ๐‘‡(๐‘ )

we obtain ๐‘‹๐‘‡๐‘‹๐‘›ฬƒ=(๐‘‹10๐‘›+1,๐‘‹11๐‘›+1,โ€ฆโ€ฆ,๐‘‹1๐‘šโˆ’1๐‘›+1,๐‘‹20๐‘›+1,๐‘‹21๐‘›+1,โ€ฆโ€ฆ,๐‘‹2๐‘šโˆ’1๐‘›+1)๐‘‡

Equation holds for ๐‘›+1.

Components of ๐‘ฟ๐’ can be Computed in terms of Components of Unknown Vector ๐‘ฟ

We substitute (1.15) into (1.14), we have ๐‘Œ๐‘‡๐‘‡(๐‘ )โ‰…๐‘‹โ€ฒ๐‘‡๐‘‡(๐‘ )+๐‘„๐‘‡๐‘‡(๐‘ )๐‘‡๐‘‡(๐‘ )๐‘‹+๐œ†1๐‘‡๐‘‡(๐‘ )๐พ1โˆซ๐‘‡(๐‘ก)๐‘‡๐‘‡(๐‘ก)๐‘‹๐‘›1๐‘‘๐‘ก+๐‘ 0๐œ†2๐‘‡๐‘‡(๐‘ )๐พ2โˆซ๐‘‡(๐‘ก)๐‘‡๐‘‡(๐‘ก)๐‘‹๐‘›2๐‘‘๐‘ก๐‘ 0

it follows that ๐‘Œ๐‘‡๐‘‡(๐‘ )โ‰…๐‘‹โ€ฒ๐‘‡๐‘‡(๐‘ )+(๐‘„ฬƒ ๐‘‡(๐‘ ))๐‘‡๐‘‹+๐œ†1๐‘‡๐‘‡(๐‘ )๐พ1๐‘‹ฬƒ๐‘›1โˆซ๐‘‡(๐‘ก)๐‘‘๐‘ก+๐œ†2๐‘‡๐‘‡(๐‘ )๐พ2๐ท๐‘‹๐‘›2๐‘ 0

Using Operational matrix ๐‘ƒ,

๐‘Œ๐‘‡๐‘‡(๐‘ )โ‰…๐‘‹โ€ฒ๐‘‡๐‘‡(๐‘ )+๐‘‹๐‘‡๐‘„ฬƒ ๐‘‡(๐‘ )+๐œ†1๐‘‡๐‘‡(๐‘ )๐พ1๐‘‹ฬƒ๐‘›1๐‘ƒ๐‘‡(๐‘ )+๐œ†2(๐พ2๐ท๐‘‹๐‘›2)๐‘‡๐‘‡(๐‘ )

In which ๐œ†1๐พ1๐‘‹ฬƒ๐‘›1๐‘ƒ is a 2๐‘šร—2๐‘š matrix

๐‘‡๐‘‡(๐‘ )๐œ†1๐พ1๐‘‹ฬƒ๐‘›1๐‘ƒ๐‘‡(๐‘ )โ‰…๐‘‹๐‘›1๐‘‡ฬ‚๐‘‡(๐‘ )

Where ๐‘‹ฬƒ๐‘›1 is an 2๐‘š-vector with components equal to the diagonal entries of the matrix ๐œ†1๐พ1๐‘‹ฬƒ๐‘›1๐‘ƒ.

๐‘Œ๐‘‡๐‘‡(๐‘ )โ‰…๐‘‹โ€ฒ๐‘‡๐‘‡(๐‘ )+๐‘‹๐‘‡๐‘„ฬƒ ๐‘‡(๐‘ )+๐‘‹๐‘›1๐‘‡ฬ‚๐‘‡(๐‘ )+๐œ†2(๐พ2๐ท๐‘‹๐‘›2)๐‘‡๐‘‡(+๐‘„ฬƒ ๐‘‹+๐‘‹๐‘›1ฬ‚+ ๐œ†2๐พ2๐ท๐‘‹๐‘›2โ‰…๐‘Œ

Where ๐‘„ฬƒ is a diagonal matrix, so ๐‘„ฬƒ ๐‘‡=๐‘„ฬƒ.

๐‘‹โ€ฒ must be computed in terms of ๐‘‹. ๐‘ฅ(๐‘ )โˆ’๐‘ฅ(0)=โˆซ๐‘ฅโ€ฒ(๐œ)๐‘‘๐œ๐‘ 0

โ‰…โˆซ๐‘‹โ€ฒ๐‘‡๐‘‡(๐œ)๐‘‘๐œ๐‘ 0 โ‰…๐‘‹โ€ฒ๐‘‡๐‘ƒ๐‘‡(๐‘ ) ๐‘ฅ(๐‘ )โ‰…๐‘‹โ€ฒ๐‘‡๐‘ƒ๐‘‡(๐‘ )+๐‘‹0๐‘‡๐‘‡(๐‘ )

Where ๐‘‹0 is the 2๐‘š- vector of the form

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๐‘‹0=[๐‘ฅ0,๐‘ฅ0,โ€ฆ๐‘ฅ0]๐‘‡

Consequently,

๐‘‹โ‰…๐‘ƒ๐‘‡๐‘‹โ€ฒ+๐‘‹0

Now, combining (1.19) and (1.20) and replacing โ‰… with =, it follows that

(๐ผ+๐‘ƒ๐‘‡๐‘„ฬƒ)๐‘‹+๐‘ƒ๐‘‡๐‘‹๐‘›1ฬ‚+๐œ†2๐‘ƒ๐‘‡๐พ2๐ท๐‘‹๐‘›2โ‰…๐‘ƒ๐‘‡๐‘Œ+๐‘‹0

Equation is a nonlinear system of 2๐‘š algebraic equations for the 2๐‘š unknowns ๐‘‹10,๐‘‹11,โ€ฆ๐‘‹1๐‘šโˆ’1,๐‘‹20,๐‘‹21,โ€ฆ๐‘‹2๐‘šโˆ’1.

Components of ๐‘‹๐‘‡=(๐‘‹1๐‘‡ ๐‘‹2๐‘‡) can be obtainbed by an iterative method.

Hence, an approximate solution ๐‘ฅ(๐‘ )โ‰…๐‘‹๐‘‡๐‘‡(๐‘ )

๐‘ฅ(๐‘ )โ‰…๐‘‹1๐‘‡๐‘‡1(๐‘ )+๐‘‹2๐‘‡๐‘‡2(๐‘ )

Can be computed for equation (1.14) without using any projection method.

Conclusion

We investigated the numerical solution of nonlinear and singularly perturbed for Vulture integro-differential equations. Also, numerical solution of high-order and fractional nonlinear Volterra-Fredholm integro-differential equations and its error analysis are discussed. Finally, some numerical results of integro-differential equations are presented to illustrated the efficiency and accuracy of the proposed methods.

Reference

1. G.Yu.Mekhtieva, V.R.Ibrahimov โ€œOn one numerical method for solution of integro-differential equationsโ€, Vestnik BSU, ser.phys.-math. Scien., 2003, No3, pp.21-27.(Russian).

2. H.Brunner, โ€œCollection method for Volterra integral and Relation Functional Equationsโ€, Cambridge University Press, Cambridge,2004.

3. P.Darania, E.Abadian, โ€œA method for the numerical solution of the integro-differential equationsโ€, Appl.Math. and Comput. 188(2007) 657-668.

4. B. Ahmad, S. Siva Sundaram, Existence Results For Nonlinear Impulsive Hybrid Boundary Value Problems involving Fractional Differential Equations, Non linear Analysis, hybrid System, 3(2009).

5. Z.B. Bai, H.S. Lii, Positive Solutions Of Boundary Valuve problems Of Nonlinear Fractional Differential Equations, J. Math Anal.Appl.311(2005)\

6. v. Lakshmikantham, D.D. Bainov And P.S. Simeonov, Theory Of Impulsive Differential Equations, modern Applied Mathematics (1989).

7. K.S. Miller, B.Ross, An Introduction To The Fractional Caculus And Fractional Differential Equations, Wiley, New york, 1993

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