5.2 Integración Numérica-Arellano Millán Carlos Daniel | C# Online Compiler

5.2 Integración Numérica-Arellano Millán Carlos Daniel by Carlos_millan4

using System;
					
public class Program
{
	public static void Main()
	{
		int accion;
            do
            {
                MostrarMenu();
                accion = AccionMenu();
                switch (accion)
                {
                    case 1:
                        Problema1();
                        break;
                    case 2:
                        Problema2();
                        break;
                    case 3:
                        Problema3();
                        break;
                }
                
                Console.Clear();
            } while (accion != 0);
           
        }
        //Declaracion de métodos
        static void MostrarMenu()
        {
            Console.WriteLine("M E N U");
            Console.WriteLine("1 - 3x^2 dx");
            Console.WriteLine("2 - (x+(2x^2)-(x^3)+(5x^4)) dx");
            Console.WriteLine("3 - (2x+1)/((x^2)+x) dx");
            Console.WriteLine("0 - Salir");
        }
        static int AccionMenu()
        {
            int accion;
            do
            {
                Console.Write("Ingrese la accion:");
                accion = Convert.ToInt32(Console.ReadLine());
            } while (accion < 0 || accion > 3);

            return accion;
        }

        static void Problema1()
        {
            Console.Clear();
            int accion;
            do
            {
                Console.WriteLine("M E N U");
                Console.WriteLine("1 - Metodo Trapecio");
                Console.WriteLine("2 - Metodo 1/3");
                Console.WriteLine("3 - Metodo 3/8");
                
                accion = AccionMenu();
                switch (accion)
                {
                    case 1:
                        Console.Clear();
                        Console.WriteLine("METODO TRAPECIO");

                        double a, b, h;
                        int n;
                        Console.Write("Valor del Limite inferior en a:");
                        a = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Ingrese N cantidad de numeros:");
                        n = Convert.ToInt32(Console.ReadLine());
                        Console.WriteLine();
                        h = (b - a) / n;
                        Console.WriteLine("El valor de h es:{0}", h);
                        Console.WriteLine();

                        Console.Clear();


                        //Fila X
                        double x = 0;
                        double[] VectorX = new double[n];
                        for (int i = 0; i < VectorX.Length; i++)
                        {

                            x = x + h;
                            VectorX[i] = x;
                        }

                        //Fila f(x)
                        double fx;
                        double[] Vectorfx = new double[n];
                        for (int i = 0; i < Vectorfx.Length; i++)
                        {
                            fx = 3 * Math.Pow(VectorX[i], 2);
                            Vectorfx[i] = fx;
                        }

                        //Fila 2(f(x))
                        double fxx;
                        double[] Vectorfxx = new double[n];
                        for (int i = 0; i < Vectorfxx.Length; i++)
                        {
                            if (i == Vectorfxx.Length - 1)
                            {
                                fxx = Vectorfx[i];
                                Vectorfxx[i] = fxx;
                            }
                            else
                            {
                                fxx = 2 * Vectorfx[i];
                                Vectorfxx[i] = fxx;
                            }
                        }

                        //Sumatoria  
                        double Σ = 0;
                        for (int i = 0; i < Vectorfxx.Length; i++)
                        {
                            Σ = Σ + Vectorfxx[i];
                        }
                        
                        double Resultado;
                        Resultado = h * Σ / 2;

                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|N={2}|h={3}|",a,b,n,h);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla = new double[n];
                        int c = 1;
                        for (int i = 0; i < Tabla.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c.ToString("00"), VectorX[i].ToString("0.00"), Vectorfx[i].ToString("00.00"), Vectorfxx[i].ToString("00.00"));
                            c = c + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ.ToString("0.00"));

                        Console.WriteLine("|Resultado|=|{0}|", Resultado.ToString("0.00"));
                        break;
                    case 2:
                        Console.Clear();
                        Console.WriteLine("METODO SIMPSON 1/3");
                        double a2, b2, h2;
                        int n2 = 2;

                        Console.Write("Valor del Limite inferior en a:");
                        a2 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b2 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        h2 = (b2 - a2) / 2;
                        Console.Clear();

                        //Fila X
                        double x2 = 0;
                        double[] VectorX2 = new double[n2];
                        for (int i = 0; i < VectorX2.Length; i++)
                        {
                            x2 = x2 + h2;
                            VectorX2[i] = x2;
                        }

                        //Fila f(x)
                        double fx2;
                        double[] Vectorfx2 = new double[n2];
                        for (int i = 0; i < Vectorfx2.Length; i++)
                        {
                            fx2 = 3 * Math.Pow(VectorX2[i], 2);
                            Vectorfx2[i] = fx2;
                        }

                        //Fila 2(f(x))
                        double fxx2;
                        double[] Vectorfxx2 = new double[n2];
                        for (int i = 0; i < Vectorfxx2.Length; i++)
                        {
                            if (i == Vectorfxx2.Length - 1)
                            {
                                fxx2 = Vectorfx2[i];
                                Vectorfxx2[i] = fxx2;
                            }
                            else
                            {
                                fxx2 = 4 * Vectorfx2[i];
                                Vectorfxx2[i] = fxx2;
                            }
                        }

                        //Sumatoria  
                        double Σ2 = 0;
                        for (int i = 0; i < Vectorfxx2.Length; i++)
                        {
                            Σ2 = Σ2 + Vectorfxx2[i];
                        }

                        double Resultado2;
                        Resultado2 = h2 * Σ2 / 3;

                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|h={2}|", a2, b2, h2);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla2 = new double[n2];
                        int c2 = 1;
                        for (int i = 0; i < Tabla2.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c2.ToString("00"), VectorX2[i].ToString("0.00"), Vectorfx2[i].ToString("00.00"), Vectorfxx2[i].ToString("00.00"));
                            c2 = c2 + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ2.ToString("00.00"));

                        Console.WriteLine("|Resultado|=|{0}|", Resultado2.ToString("00.00"));
                        break;
                    case 3:
                        Console.Clear();
                        Console.WriteLine("METODO SIMPSON 3/8");
                        double a3, b3, h3;
                        int n3;
                        Console.Write("Valor del Limite inferior en a:");
                        a3 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b3 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Ingrese N cantidad de numeros:");
                        n3 = Convert.ToInt32(Console.ReadLine());
                        Console.WriteLine();
                        h3 = (b3 - a3) / n3;
                        Console.WriteLine("El valor de h es:{0}", h3);
                        Console.WriteLine();
                        Console.Clear();

                        //Fila X
                        double x3 = 0;
                        double[] VectorX3 = new double[n3];
                        for (int i = 0; i < VectorX3.Length; i++)
                        {

                            x3 = x3 + h3;
                            VectorX3[i] = x3;
                        }

                        //Fila f(x)
                        double fx3;
                        double[] Vectorfx3 = new double[n3];
                        for (int i = 0; i < Vectorfx3.Length; i++)
                        {
                            fx3 = 3 * Math.Pow(VectorX3[i], 2);
                            Vectorfx3[i] = fx3;
                        }

                        //Fila 3(f(x))
                        double fxx3;
                        double[] Vectorfxx3 = new double[n3];
                        for (int i = 0; i < Vectorfxx3.Length; i++)
                        {
                            if (i == Vectorfxx3.Length - 1)
                            {
                                fxx3 = Vectorfx3[i];
                                Vectorfxx3[i] = fxx3;
                            }
                            else
                            {
                                fxx3 = 3 * Vectorfx3[i];
                                Vectorfxx3[i] = fxx3;
                            }

                        }

                        //Sumatoria  
                        double Σ3 = 0;
                        for (int i = 0; i < Vectorfxx3.Length; i++)
                        {
                            Σ3 = Σ3 + Vectorfxx3[i];
                        }

                        double Resultado3;
                        Resultado3 = 3 * h3 * Σ3 / 8;

                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|N={2}|h={3}|", a3, b3, n3, h3);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla3 = new double[n3];
                        int c3 = 1;
                        for (int i = 0; i < Tabla3.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c3.ToString("00"), VectorX3[i].ToString("0.00"), Vectorfx3[i].ToString("00.00"), Vectorfxx3[i].ToString("00.00"));
                            c3 = c3 + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ3.ToString("00.000"));

                        Console.WriteLine("|Resultado|=|{0}|", Resultado3.ToString("00.00000"));
                        break;
                }
                Console.Clear();
            } while (accion != 0);
            Console.Clear();
            
            return;
        }

        static void Problema2()
        {
            Console.Clear();
            int accion;
            do
            {
                Console.WriteLine("M E N U");
                Console.WriteLine("1 - Metodo Trapecio");
                Console.WriteLine("2 - Metodo 1/3");
                Console.WriteLine("3 - Metodo 3/8");

                accion = AccionMenu();
                switch (accion)
                {
                    case 1:
                        Console.Clear();
                        Console.WriteLine("METODO TRAPECIO");

                        double a, b, h;
                        int n;
                        Console.Write("Valor del Limite inferior en a:");
                        a = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Ingrese N cantidad de numeros:");
                        n = Convert.ToInt32(Console.ReadLine());
                        Console.WriteLine();
                        h = (b - a) / n;
                        Console.WriteLine("El valor de h es:{0}", h);
                        Console.WriteLine();
                        Console.Clear();

                        //Fila X
                        double x = 0;
                        double[] VectorX = new double[n];
                        for (int i = 0; i < VectorX.Length; i++)
                        {
                            x = x + h;
                            VectorX[i] = x;
                        }

                        //Fila f(x)
                        double fx;
                        double[] Vectorfx = new double[n];
                        for (int i = 0; i < Vectorfx.Length; i++)
                        {                           
                            fx = VectorX[i] + 2 * Math.Pow(VectorX[i], 2) - Math.Pow(VectorX[i],3) + 5 * Math.Pow(VectorX[i],4);
                            Vectorfx[i] = fx;
                        }

                        //Fila 2(f(x))
                        double fxx;
                        double[] Vectorfxx = new double[n];
                        for (int i = 0; i < Vectorfxx.Length; i++)
                        {
                            if (i == Vectorfxx.Length - 1)
                            {
                                fxx = Vectorfx[i];
                                Vectorfxx[i] = fxx;
                            }
                            else
                            {
                                fxx = 2 * Vectorfx[i];
                                Vectorfxx[i] = fxx;
                            }

                        }

                        //Sumatoria  
                        double Σ = 0;
                        for (int i = 0; i < Vectorfxx.Length; i++)
                        {
                            Σ = Σ + Vectorfxx[i];
                        }

                        double Resultado;
                        Resultado = h * Σ / 2;

                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|N={2}|h={3}|", a, b, n, h);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   |   F(x)   |  2f(x)  |");
                        double[] Tabla = new double[n];
                        int c = 1;
                        for (int i = 0; i < Tabla.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c.ToString("00"), VectorX[i].ToString("0.00"), Vectorfx[i].ToString("00000.00"), Vectorfxx[i].ToString("00000.00"));
                            c = c + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ.ToString("0.000"));

                        Console.WriteLine("|Resultado|=|{0}|", Resultado.ToString("0.000"));
                        break;
                    case 2:
                        Console.Clear();
                        Console.WriteLine("METODO SIMPSON 1/3");
                        double a2, b2, h2;
                        int n2 = 2;

                        Console.Write("Valor del Limite inferior en a:");
                        a2 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b2 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        h2 = (b2 - a2) / 2;
                        Console.Clear();
                        //Fila X
                        double x2 = 0;
                        double[] VectorX2 = new double[n2];
                        for (int i = 0; i < VectorX2.Length; i++)
                        {
                            x2 = x2 + h2;
                            VectorX2[i] = x2;
                        }

                        //Fila f(x)
                        double fx2;
                        double[] Vectorfx2 = new double[n2];
                        for (int i = 0; i < Vectorfx2.Length; i++)
                        {
                            fx2 = VectorX2[i] + 2 * Math.Pow(VectorX2[i], 2) - Math.Pow(VectorX2[i], 3) + 5 * Math.Pow(VectorX2[i], 4);
                            Vectorfx2[i] = fx2;
                        }

                        //Fila 2(f(x))
                        double fxx2;
                        double[] Vectorfxx2 = new double[n2];
                        for (int i = 0; i < Vectorfxx2.Length; i++)
                        {
                            if (i == Vectorfxx2.Length - 1)
                            {
                                fxx2 = Vectorfx2[i];
                                Vectorfxx2[i] = fxx2;
                            }
                            else
                            {
                                fxx2 = 4 * Vectorfx2[i];
                                Vectorfxx2[i] = fxx2;
                            }
                        }

                        //Sumatoria  
                        double Σ2 = 0;
                        for (int i = 0; i < Vectorfxx2.Length; i++)
                        {
                            Σ2 = Σ2 + Vectorfxx2[i];
                        }                   

                        double Resultado2;
                        Resultado2 = h2 * Σ2 / 3;

                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|h={2}|", a2, b2, h2);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla2 = new double[n2];
                        int c2 = 1;
                        for (int i = 0; i < Tabla2.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c2.ToString("00"), VectorX2[i].ToString("0.00"), Vectorfx2[i].ToString("00.00"), Vectorfxx2[i].ToString("00.00"));
                            c2 = c2 + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ2.ToString("00.00"));

                        Console.WriteLine("|Resultado|=|{0}|", Resultado2.ToString("00.00"));
                        break;
                    case 3:
                        Console.Clear();
                        Console.WriteLine("METODO SIMPSON 3/8");
                        double a3, b3, h3;
                        int n3;
                        Console.Write("Valor del Limite inferior en a:");
                        a3 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b3 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Ingrese N cantidad de numeros:");
                        n3 = Convert.ToInt32(Console.ReadLine());
                        Console.WriteLine();
                        h3 = (b3 - a3) / n3;
                        Console.WriteLine("El valor de h es:{0}", h3);
                        Console.WriteLine();
                        Console.Clear();

                        //Fila X
                        double x3 = 0;
                        double[] VectorX3 = new double[n3];
                        for (int i = 0; i < VectorX3.Length; i++)
                        {

                            x3 = x3 + h3;
                            VectorX3[i] = x3;
                        }

                        //Fila f(x)
                        double fx3;
                        double[] Vectorfx3 = new double[n3];
                        for (int i = 0; i < Vectorfx3.Length; i++)
                        {                            
                            fx3 = VectorX3[i] + 2 * Math.Pow(VectorX3[i], 2) - Math.Pow(VectorX3[i], 3) + 5 * Math.Pow(VectorX3[i], 4);
                            Vectorfx3[i] = fx3;
                        }

                        //Fila 3(f(x))
                        double fxx3;
                        double[] Vectorfxx3 = new double[n3];
                        for (int i = 0; i < Vectorfxx3.Length; i++)
                        {
                            if (i == Vectorfxx3.Length - 1)
                            {
                                fxx3 = Vectorfx3[i];
                                Vectorfxx3[i] = fxx3;
                            }
                            else
                            {
                                fxx3 = 3 * Vectorfx3[i];
                                Vectorfxx3[i] = fxx3;
                            }

                        }

                        //Sumatoria  
                        double Σ3 = 0;
                        for (int i = 0; i < Vectorfxx3.Length; i++)
                        {
                            Σ3 = Σ3 + Vectorfxx3[i];
                        }

                        double Resultado3;
                        Resultado3 = 3 * h3 * Σ3 / 8;

                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|N={2}|h={3}|",a3,b3,n3,h3);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla3 = new double[n3];
                        int c3 = 1;
                        for (int i = 0; i < Tabla3.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c3.ToString("00"), VectorX3[i].ToString("0.00"), Vectorfx3[i].ToString("00.00"), Vectorfxx3[i].ToString("00.00"));
                            c3 = c3 + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ3.ToString("00.000"));

                        Console.WriteLine("|Resultado|=|{0}|", Resultado3.ToString("00.00000"));
                        break;
                }
                Console.Clear();
            } while (accion != 0);
            Console.Clear();
            return;
        }

        static void Problema3()
        {
            Console.Clear();
            int accion;
            do
            {
                Console.WriteLine("M E N U");
                Console.WriteLine("1 - Metodo Trapecio");
                Console.WriteLine("2 - Metodo 1/3");
                Console.WriteLine("3 - Metodo 3/8");

                accion = AccionMenu();
                switch (accion)
                {
                    case 1:
                        Console.Clear();
                        Console.WriteLine("METODO TRAPECIO");

                        double a, b, h;
                        int n;
                        Console.Write("Valor del Limite inferior en a:");
                        a = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Ingrese N cantidad de numeros:");
                        n = Convert.ToInt32(Console.ReadLine());
                        Console.WriteLine();
                        h = (b - a) / n;
                        Console.WriteLine("El valor de h es:{0}", h);
                        Console.WriteLine();
                        Console.Clear();

                        //Fila X
                        double x = 0;
                        double[] VectorX = new double[n];
                        for (int i = 0; i < VectorX.Length; i++)
                        {

                            x = x + h;
                            VectorX[i] = x;
                        }

                        //Fila f(x)
                        double fx;
                        double[] Vectorfx = new double[n];
                        for (int i = 0; i < Vectorfx.Length; i++)
                        {
                            //((2 * x) + 1) / ((x * x) + x);
                            fx = ((2*VectorX[i])+1)/(Math.Pow(VectorX[i],2)+VectorX[i]);
                            Vectorfx[i] = fx;
                        }

                        //Fila 2(f(x))
                        double fxx;
                        double[] Vectorfxx = new double[n];
                        for (int i = 0; i < Vectorfxx.Length; i++)
                        {
                            if (i == Vectorfxx.Length - 1)
                            {
                                fxx = Vectorfx[i];
                                Vectorfxx[i] = fxx;
                            }
                            else
                            {
                                fxx = 2 * Vectorfx[i];
                                Vectorfxx[i] = fxx;
                            }

                        }

                        //Sumatoria  
                        double Σ = 0;
                        for (int i = 0; i < Vectorfxx.Length; i++)
                        {
                            Σ = Σ + Vectorfxx[i];
                        }

                        double Resultado;
                        Resultado = h * Σ / 2;

                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|N={2}|h={3}|",a,b,n,h);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla = new double[n];
                        int c = 1;
                        for (int i = 0; i < Tabla.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c.ToString("00"), VectorX[i].ToString("0.00"), Vectorfx[i].ToString("00.00"), Vectorfxx[i].ToString("00.00"));
                            c = c + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ.ToString("0.000"));

                        Console.WriteLine("|Resultado|=|{0}|", Resultado.ToString("0.000"));
                        break;
                    case 2:
                        Console.Clear();
                        Console.WriteLine("METODO SIMPSON 1/3");
                        double a2, b2, h2;
                        int n2 = 2;

                        Console.Write("Valor del Limite inferior en a:");
                        a2 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b2 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        h2 = (b2 - a2) / 2;
                        Console.Clear();
                        //Fila X
                        double x2 = 0;
                        double[] VectorX2 = new double[n2];
                        for (int i = 0; i < VectorX2.Length; i++)
                        {
                            x2 = x2 + h2;
                            VectorX2[i] = x2;
                        }

                        //Fila f(x)
                        double fx2;
                        double[] Vectorfx2 = new double[n2];
                        for (int i = 0; i < Vectorfx2.Length; i++)
                        {
                            fx2 = ((2 * VectorX2[i]) + 1) / (Math.Pow(VectorX2[i], 2) + VectorX2[i]);
                            Vectorfx2[i] = fx2;
                        }

                        //Fila 2(f(x))
                        double fxx2;
                        double[] Vectorfxx2 = new double[n2];
                        for (int i = 0; i < Vectorfxx2.Length; i++)
                        {
                            if (i == Vectorfxx2.Length - 1)
                            {
                                fxx2 = Vectorfx2[i];
                                Vectorfxx2[i] = fxx2;
                            }
                            else
                            {
                                fxx2 = 4 * Vectorfx2[i];
                                Vectorfxx2[i] = fxx2;
                            }
                        }

                        //Sumatoria  
                        double Σ2 = 0;
                        for (int i = 0; i < Vectorfxx2.Length; i++)
                        {
                            Σ2 = Σ2 + Vectorfxx2[i];
                        }

                        double Resultado2;
                        Resultado2 = h2 * Σ2 / 3;

                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|h={2}|", a2, b2, h2);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla2 = new double[n2];
                        int c2 = 1;
                        for (int i = 0; i < Tabla2.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c2.ToString("00"), VectorX2[i].ToString("0.00"), Vectorfx2[i].ToString("00.00"), Vectorfxx2[i].ToString("00.00"));
                            c2 = c2 + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ2.ToString("00.00"));

                        Console.WriteLine("|Resultado|=|{0}|", Resultado2.ToString("00.00"));
                        break;
                    case 3:
                        Console.Clear();
                        Console.WriteLine("METODO SIMPSON 3/8");
                        double a3, b3, h3;
                        int n3;
                        Console.Write("Valor del Limite inferior en a:");
                        a3 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b3 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Ingrese N cantidad de numeros:");
                        n3 = Convert.ToInt32(Console.ReadLine());
                        Console.WriteLine();
                        h3 = (b3 - a3) / n3;
                        Console.WriteLine("El valor de h es:{0}", h3);
                        Console.WriteLine();
                        Console.Clear();

                        //Fila X
                        double x3 = 0;
                        double[] VectorX3 = new double[n3];
                        for (int i = 0; i < VectorX3.Length; i++)
                        {

                            x3 = x3 + h3;
                            VectorX3[i] = x3;
                        }

                        //Fila f(x)
                        double fx3;
                        double[] Vectorfx3 = new double[n3];
                        for (int i = 0; i < Vectorfx3.Length; i++)
                        {
                            fx3 = ((2 * VectorX3[i]) + 1) / (Math.Pow(VectorX3[i], 2) + VectorX3[i]);
                            Vectorfx3[i] = fx3;
                        }

                        //Fila 3(f(x))
                        double fxx3;
                        double[] Vectorfxx3 = new double[n3];
                        for (int i = 0; i < Vectorfxx3.Length; i++)
                        {
                            if (i == Vectorfxx3.Length - 1)
                            {
                                fxx3 = Vectorfx3[i];
                                Vectorfxx3[i] = fxx3;
                            }
                            else
                            {
                                fxx3 = 3 * Vectorfx3[i];
                                Vectorfxx3[i] = fxx3;
                            }

                        }

                        //Sumatoria  
                        double Σ3 = 0;
                        for (int i = 0; i < Vectorfxx3.Length; i++)
                        {
                            Σ3 = Σ3 + Vectorfxx3[i];
                        }
                       


                        double Resultado3;
                        Resultado3 = 3 * h3 * Σ3 / 8;

                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|N={2}|h={3}|",a3,b3,n3,h3);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla3 = new double[n3];
                        int c3 = 1;
                        for (int i = 0; i < Tabla3.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c3.ToString("00"), VectorX3[i].ToString("0.00"), Vectorfx3[i].ToString("00.00"), Vectorfxx3[i].ToString("00.00"));
                            c3 = c3 + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ3.ToString("00.000"));

                        Console.WriteLine("|Resultado|=|{0}|", Resultado3.ToString("00.00000"));
                        break;
                }
                Console.Clear();
            } while (accion != 0);
            Console.Clear();
            return;
        }
    }

​x
 
using System;
                    
public class Program
{
    public static void Main()
    {
        int accion;
            do
            {
                MostrarMenu();
                accion = AccionMenu();
                switch (accion)
                {
                    case 1:
                        Problema1();
                        break;
                    case 2:
                        Problema2();
                        break;
                    case 3:
                        Problema3();
                        break;
                }
                
                Console.Clear();
            } while (accion != 0);
           
        }
        //Declaracion de métodos
        static void MostrarMenu()
        {
            Console.WriteLine("M E N U");
            Console.WriteLine("1 - 3x^2 dx");
            Console.WriteLine("2 - (x+(2x^2)-(x^3)+(5x^4)) dx");
            Console.WriteLine("3 - (2x+1)/((x^2)+x) dx");
            Console.WriteLine("0 - Salir");
        }
        static int AccionMenu()
        {
            int accion;
            do
            {
                Console.Write("Ingrese la accion:");
                accion = Convert.ToInt32(Console.ReadLine());
            } while (accion < 0 || accion > 3);
​
            return accion;
        }
​
        static void Problema1()
        {
            Console.Clear();
            int accion;
            do
            {
                Console.WriteLine("M E N U");
                Console.WriteLine("1 - Metodo Trapecio");
                Console.WriteLine("2 - Metodo 1/3");
                Console.WriteLine("3 - Metodo 3/8");
                
                accion = AccionMenu();
                switch (accion)
                {
                    case 1:
                        Console.Clear();
                        Console.WriteLine("METODO TRAPECIO");
​
                        double a, b, h;
                        int n;
                        Console.Write("Valor del Limite inferior en a:");
                        a = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Ingrese N cantidad de numeros:");
                        n = Convert.ToInt32(Console.ReadLine());
                        Console.WriteLine();
                        h = (b - a) / n;
                        Console.WriteLine("El valor de h es:{0}", h);
                        Console.WriteLine();
​
                        Console.Clear();
​
​
                        //Fila X
                        double x = 0;
                        double[] VectorX = new double[n];
                        for (int i = 0; i < VectorX.Length; i++)
                        {
​
                            x = x + h;
                            VectorX[i] = x;
                        }
​
                        //Fila f(x)
                        double fx;
                        double[] Vectorfx = new double[n];
                        for (int i = 0; i < Vectorfx.Length; i++)
                        {
                            fx = 3 * Math.Pow(VectorX[i], 2);
                            Vectorfx[i] = fx;
                        }
​
                        //Fila 2(f(x))
                        double fxx;
                        double[] Vectorfxx = new double[n];
                        for (int i = 0; i < Vectorfxx.Length; i++)
                        {
                            if (i == Vectorfxx.Length - 1)
                            {
                                fxx = Vectorfx[i];
                                Vectorfxx[i] = fxx;
                            }
                            else
                            {
                                fxx = 2 * Vectorfx[i];
                                Vectorfxx[i] = fxx;
                            }
                        }
​
                        //Sumatoria  
                        double Σ = 0;
                        for (int i = 0; i < Vectorfxx.Length; i++)
                        {
                            Σ = Σ + Vectorfxx[i];
                        }
                        
                        double Resultado;
                        Resultado = h * Σ / 2;
​
                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|N={2}|h={3}|",a,b,n,h);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla = new double[n];
                        int c = 1;
                        for (int i = 0; i < Tabla.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c.ToString("00"), VectorX[i].ToString("0.00"), Vectorfx[i].ToString("00.00"), Vectorfxx[i].ToString("00.00"));
                            c = c + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ.ToString("0.00"));
​
                        Console.WriteLine("|Resultado|=|{0}|", Resultado.ToString("0.00"));
                        break;
                    case 2:
                        Console.Clear();
                        Console.WriteLine("METODO SIMPSON 1/3");
                        double a2, b2, h2;
                        int n2 = 2;
​
                        Console.Write("Valor del Limite inferior en a:");
                        a2 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b2 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        h2 = (b2 - a2) / 2;
                        Console.Clear();
​
                        //Fila X
                        double x2 = 0;
                        double[] VectorX2 = new double[n2];
                        for (int i = 0; i < VectorX2.Length; i++)
                        {
                            x2 = x2 + h2;
                            VectorX2[i] = x2;
                        }
​
                        //Fila f(x)
                        double fx2;
                        double[] Vectorfx2 = new double[n2];
                        for (int i = 0; i < Vectorfx2.Length; i++)
                        {
                            fx2 = 3 * Math.Pow(VectorX2[i], 2);
                            Vectorfx2[i] = fx2;
                        }
​
                        //Fila 2(f(x))
                        double fxx2;
                        double[] Vectorfxx2 = new double[n2];
                        for (int i = 0; i < Vectorfxx2.Length; i++)
                        {
                            if (i == Vectorfxx2.Length - 1)
                            {
                                fxx2 = Vectorfx2[i];
                                Vectorfxx2[i] = fxx2;
                            }
                            else
                            {
                                fxx2 = 4 * Vectorfx2[i];
                                Vectorfxx2[i] = fxx2;
                            }
                        }
​
                        //Sumatoria  
                        double Σ2 = 0;
                        for (int i = 0; i < Vectorfxx2.Length; i++)
                        {
                            Σ2 = Σ2 + Vectorfxx2[i];
                        }
​
                        double Resultado2;
                        Resultado2 = h2 * Σ2 / 3;
​
                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|h={2}|", a2, b2, h2);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla2 = new double[n2];
                        int c2 = 1;
                        for (int i = 0; i < Tabla2.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c2.ToString("00"), VectorX2[i].ToString("0.00"), Vectorfx2[i].ToString("00.00"), Vectorfxx2[i].ToString("00.00"));
                            c2 = c2 + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ2.ToString("00.00"));
​
                        Console.WriteLine("|Resultado|=|{0}|", Resultado2.ToString("00.00"));
                        break;
                    case 3:
                        Console.Clear();
                        Console.WriteLine("METODO SIMPSON 3/8");
                        double a3, b3, h3;
                        int n3;
                        Console.Write("Valor del Limite inferior en a:");
                        a3 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b3 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Ingrese N cantidad de numeros:");
                        n3 = Convert.ToInt32(Console.ReadLine());
                        Console.WriteLine();
                        h3 = (b3 - a3) / n3;
                        Console.WriteLine("El valor de h es:{0}", h3);
                        Console.WriteLine();
                        Console.Clear();
​
                        //Fila X
                        double x3 = 0;
                        double[] VectorX3 = new double[n3];
                        for (int i = 0; i < VectorX3.Length; i++)
                        {
​
                            x3 = x3 + h3;
                            VectorX3[i] = x3;
                        }
​
                        //Fila f(x)
                        double fx3;
                        double[] Vectorfx3 = new double[n3];
                        for (int i = 0; i < Vectorfx3.Length; i++)
                        {
                            fx3 = 3 * Math.Pow(VectorX3[i], 2);
                            Vectorfx3[i] = fx3;
                        }
​
                        //Fila 3(f(x))
                        double fxx3;
                        double[] Vectorfxx3 = new double[n3];
                        for (int i = 0; i < Vectorfxx3.Length; i++)
                        {
                            if (i == Vectorfxx3.Length - 1)
                            {
                                fxx3 = Vectorfx3[i];
                                Vectorfxx3[i] = fxx3;
                            }
                            else
                            {
                                fxx3 = 3 * Vectorfx3[i];
                                Vectorfxx3[i] = fxx3;
                            }
​
                        }
​
                        //Sumatoria  
                        double Σ3 = 0;
                        for (int i = 0; i < Vectorfxx3.Length; i++)
                        {
                            Σ3 = Σ3 + Vectorfxx3[i];
                        }
​
                        double Resultado3;
                        Resultado3 = 3 * h3 * Σ3 / 8;
​
                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|N={2}|h={3}|", a3, b3, n3, h3);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla3 = new double[n3];
                        int c3 = 1;
                        for (int i = 0; i < Tabla3.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c3.ToString("00"), VectorX3[i].ToString("0.00"), Vectorfx3[i].ToString("00.00"), Vectorfxx3[i].ToString("00.00"));
                            c3 = c3 + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ3.ToString("00.000"));
​
                        Console.WriteLine("|Resultado|=|{0}|", Resultado3.ToString("00.00000"));
                        break;
                }
                Console.Clear();
            } while (accion != 0);
            Console.Clear();
            
            return;
        }
​
        static void Problema2()
        {
            Console.Clear();
            int accion;
            do
            {
                Console.WriteLine("M E N U");
                Console.WriteLine("1 - Metodo Trapecio");
                Console.WriteLine("2 - Metodo 1/3");
                Console.WriteLine("3 - Metodo 3/8");
​
                accion = AccionMenu();
                switch (accion)
                {
                    case 1:
                        Console.Clear();
                        Console.WriteLine("METODO TRAPECIO");
​
                        double a, b, h;
                        int n;
                        Console.Write("Valor del Limite inferior en a:");
                        a = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Ingrese N cantidad de numeros:");
                        n = Convert.ToInt32(Console.ReadLine());
                        Console.WriteLine();
                        h = (b - a) / n;
                        Console.WriteLine("El valor de h es:{0}", h);
                        Console.WriteLine();
                        Console.Clear();
​
                        //Fila X
                        double x = 0;
                        double[] VectorX = new double[n];
                        for (int i = 0; i < VectorX.Length; i++)
                        {
                            x = x + h;
                            VectorX[i] = x;
                        }
​
                        //Fila f(x)
                        double fx;
                        double[] Vectorfx = new double[n];
                        for (int i = 0; i < Vectorfx.Length; i++)
                        {                           
                            fx = VectorX[i] + 2 * Math.Pow(VectorX[i], 2) - Math.Pow(VectorX[i],3) + 5 * Math.Pow(VectorX[i],4);
                            Vectorfx[i] = fx;
                        }
​
                        //Fila 2(f(x))
                        double fxx;
                        double[] Vectorfxx = new double[n];
                        for (int i = 0; i < Vectorfxx.Length; i++)
                        {
                            if (i == Vectorfxx.Length - 1)
                            {
                                fxx = Vectorfx[i];
                                Vectorfxx[i] = fxx;
                            }
                            else
                            {
                                fxx = 2 * Vectorfx[i];
                                Vectorfxx[i] = fxx;
                            }
​
                        }
​
                        //Sumatoria  
                        double Σ = 0;
                        for (int i = 0; i < Vectorfxx.Length; i++)
                        {
                            Σ = Σ + Vectorfxx[i];
                        }
​
                        double Resultado;
                        Resultado = h * Σ / 2;
​
                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|N={2}|h={3}|", a, b, n, h);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   |   F(x)   |  2f(x)  |");
                        double[] Tabla = new double[n];
                        int c = 1;
                        for (int i = 0; i < Tabla.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c.ToString("00"), VectorX[i].ToString("0.00"), Vectorfx[i].ToString("00000.00"), Vectorfxx[i].ToString("00000.00"));
                            c = c + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ.ToString("0.000"));
​
                        Console.WriteLine("|Resultado|=|{0}|", Resultado.ToString("0.000"));
                        break;
                    case 2:
                        Console.Clear();
                        Console.WriteLine("METODO SIMPSON 1/3");
                        double a2, b2, h2;
                        int n2 = 2;
​
                        Console.Write("Valor del Limite inferior en a:");
                        a2 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b2 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        h2 = (b2 - a2) / 2;
                        Console.Clear();
                        //Fila X
                        double x2 = 0;
                        double[] VectorX2 = new double[n2];
                        for (int i = 0; i < VectorX2.Length; i++)
                        {
                            x2 = x2 + h2;
                            VectorX2[i] = x2;
                        }
​
                        //Fila f(x)
                        double fx2;
                        double[] Vectorfx2 = new double[n2];
                        for (int i = 0; i < Vectorfx2.Length; i++)
                        {
                            fx2 = VectorX2[i] + 2 * Math.Pow(VectorX2[i], 2) - Math.Pow(VectorX2[i], 3) + 5 * Math.Pow(VectorX2[i], 4);
                            Vectorfx2[i] = fx2;
                        }
​
                        //Fila 2(f(x))
                        double fxx2;
                        double[] Vectorfxx2 = new double[n2];
                        for (int i = 0; i < Vectorfxx2.Length; i++)
                        {
                            if (i == Vectorfxx2.Length - 1)
                            {
                                fxx2 = Vectorfx2[i];
                                Vectorfxx2[i] = fxx2;
                            }
                            else
                            {
                                fxx2 = 4 * Vectorfx2[i];
                                Vectorfxx2[i] = fxx2;
                            }
                        }
​
                        //Sumatoria  
                        double Σ2 = 0;
                        for (int i = 0; i < Vectorfxx2.Length; i++)
                        {
                            Σ2 = Σ2 + Vectorfxx2[i];
                        }                   
​
                        double Resultado2;
                        Resultado2 = h2 * Σ2 / 3;
​
                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|h={2}|", a2, b2, h2);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla2 = new double[n2];
                        int c2 = 1;
                        for (int i = 0; i < Tabla2.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c2.ToString("00"), VectorX2[i].ToString("0.00"), Vectorfx2[i].ToString("00.00"), Vectorfxx2[i].ToString("00.00"));
                            c2 = c2 + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ2.ToString("00.00"));
​
                        Console.WriteLine("|Resultado|=|{0}|", Resultado2.ToString("00.00"));
                        break;
                    case 3:
                        Console.Clear();
                        Console.WriteLine("METODO SIMPSON 3/8");
                        double a3, b3, h3;
                        int n3;
                        Console.Write("Valor del Limite inferior en a:");
                        a3 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b3 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Ingrese N cantidad de numeros:");
                        n3 = Convert.ToInt32(Console.ReadLine());
                        Console.WriteLine();
                        h3 = (b3 - a3) / n3;
                        Console.WriteLine("El valor de h es:{0}", h3);
                        Console.WriteLine();
                        Console.Clear();
​
                        //Fila X
                        double x3 = 0;
                        double[] VectorX3 = new double[n3];
                        for (int i = 0; i < VectorX3.Length; i++)
                        {
​
                            x3 = x3 + h3;
                            VectorX3[i] = x3;
                        }
​
                        //Fila f(x)
                        double fx3;
                        double[] Vectorfx3 = new double[n3];
                        for (int i = 0; i < Vectorfx3.Length; i++)
                        {                            
                            fx3 = VectorX3[i] + 2 * Math.Pow(VectorX3[i], 2) - Math.Pow(VectorX3[i], 3) + 5 * Math.Pow(VectorX3[i], 4);
                            Vectorfx3[i] = fx3;
                        }
​
                        //Fila 3(f(x))
                        double fxx3;
                        double[] Vectorfxx3 = new double[n3];
                        for (int i = 0; i < Vectorfxx3.Length; i++)
                        {
                            if (i == Vectorfxx3.Length - 1)
                            {
                                fxx3 = Vectorfx3[i];
                                Vectorfxx3[i] = fxx3;
                            }
                            else
                            {
                                fxx3 = 3 * Vectorfx3[i];
                                Vectorfxx3[i] = fxx3;
                            }
​
                        }
​
                        //Sumatoria  
                        double Σ3 = 0;
                        for (int i = 0; i < Vectorfxx3.Length; i++)
                        {
                            Σ3 = Σ3 + Vectorfxx3[i];
                        }
​
                        double Resultado3;
                        Resultado3 = 3 * h3 * Σ3 / 8;
​
                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|N={2}|h={3}|",a3,b3,n3,h3);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla3 = new double[n3];
                        int c3 = 1;
                        for (int i = 0; i < Tabla3.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c3.ToString("00"), VectorX3[i].ToString("0.00"), Vectorfx3[i].ToString("00.00"), Vectorfxx3[i].ToString("00.00"));
                            c3 = c3 + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ3.ToString("00.000"));
​
                        Console.WriteLine("|Resultado|=|{0}|", Resultado3.ToString("00.00000"));
                        break;
                }
                Console.Clear();
            } while (accion != 0);
            Console.Clear();
            return;
        }
​
        static void Problema3()
        {
            Console.Clear();
            int accion;
            do
            {
                Console.WriteLine("M E N U");
                Console.WriteLine("1 - Metodo Trapecio");
                Console.WriteLine("2 - Metodo 1/3");
                Console.WriteLine("3 - Metodo 3/8");
​
                accion = AccionMenu();
                switch (accion)
                {
                    case 1:
                        Console.Clear();
                        Console.WriteLine("METODO TRAPECIO");
​
                        double a, b, h;
                        int n;
                        Console.Write("Valor del Limite inferior en a:");
                        a = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Ingrese N cantidad de numeros:");
                        n = Convert.ToInt32(Console.ReadLine());
                        Console.WriteLine();
                        h = (b - a) / n;
                        Console.WriteLine("El valor de h es:{0}", h);
                        Console.WriteLine();
                        Console.Clear();
​
                        //Fila X
                        double x = 0;
                        double[] VectorX = new double[n];
                        for (int i = 0; i < VectorX.Length; i++)
                        {
​
                            x = x + h;
                            VectorX[i] = x;
                        }
​
                        //Fila f(x)
                        double fx;
                        double[] Vectorfx = new double[n];
                        for (int i = 0; i < Vectorfx.Length; i++)
                        {
                            //((2 * x) + 1) / ((x * x) + x);
                            fx = ((2*VectorX[i])+1)/(Math.Pow(VectorX[i],2)+VectorX[i]);
                            Vectorfx[i] = fx;
                        }
​
                        //Fila 2(f(x))
                        double fxx;
                        double[] Vectorfxx = new double[n];
                        for (int i = 0; i < Vectorfxx.Length; i++)
                        {
                            if (i == Vectorfxx.Length - 1)
                            {
                                fxx = Vectorfx[i];
                                Vectorfxx[i] = fxx;
                            }
                            else
                            {
                                fxx = 2 * Vectorfx[i];
                                Vectorfxx[i] = fxx;
                            }
​
                        }
​
                        //Sumatoria  
                        double Σ = 0;
                        for (int i = 0; i < Vectorfxx.Length; i++)
                        {
                            Σ = Σ + Vectorfxx[i];
                        }
​
                        double Resultado;
                        Resultado = h * Σ / 2;
​
                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|N={2}|h={3}|",a,b,n,h);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla = new double[n];
                        int c = 1;
                        for (int i = 0; i < Tabla.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c.ToString("00"), VectorX[i].ToString("0.00"), Vectorfx[i].ToString("00.00"), Vectorfxx[i].ToString("00.00"));
                            c = c + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ.ToString("0.000"));
​
                        Console.WriteLine("|Resultado|=|{0}|", Resultado.ToString("0.000"));
                        break;
                    case 2:
                        Console.Clear();
                        Console.WriteLine("METODO SIMPSON 1/3");
                        double a2, b2, h2;
                        int n2 = 2;
​
                        Console.Write("Valor del Limite inferior en a:");
                        a2 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b2 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        h2 = (b2 - a2) / 2;
                        Console.Clear();
                        //Fila X
                        double x2 = 0;
                        double[] VectorX2 = new double[n2];
                        for (int i = 0; i < VectorX2.Length; i++)
                        {
                            x2 = x2 + h2;
                            VectorX2[i] = x2;
                        }
​
                        //Fila f(x)
                        double fx2;
                        double[] Vectorfx2 = new double[n2];
                        for (int i = 0; i < Vectorfx2.Length; i++)
                        {
                            fx2 = ((2 * VectorX2[i]) + 1) / (Math.Pow(VectorX2[i], 2) + VectorX2[i]);
                            Vectorfx2[i] = fx2;
                        }
​
                        //Fila 2(f(x))
                        double fxx2;
                        double[] Vectorfxx2 = new double[n2];
                        for (int i = 0; i < Vectorfxx2.Length; i++)
                        {
                            if (i == Vectorfxx2.Length - 1)
                            {
                                fxx2 = Vectorfx2[i];
                                Vectorfxx2[i] = fxx2;
                            }
                            else
                            {
                                fxx2 = 4 * Vectorfx2[i];
                                Vectorfxx2[i] = fxx2;
                            }
                        }
​
                        //Sumatoria  
                        double Σ2 = 0;
                        for (int i = 0; i < Vectorfxx2.Length; i++)
                        {
                            Σ2 = Σ2 + Vectorfxx2[i];
                        }
​
                        double Resultado2;
                        Resultado2 = h2 * Σ2 / 3;
​
                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|h={2}|", a2, b2, h2);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla2 = new double[n2];
                        int c2 = 1;
                        for (int i = 0; i < Tabla2.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c2.ToString("00"), VectorX2[i].ToString("0.00"), Vectorfx2[i].ToString("00.00"), Vectorfxx2[i].ToString("00.00"));
                            c2 = c2 + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ2.ToString("00.00"));
​
                        Console.WriteLine("|Resultado|=|{0}|", Resultado2.ToString("00.00"));
                        break;
                    case 3:
                        Console.Clear();
                        Console.WriteLine("METODO SIMPSON 3/8");
                        double a3, b3, h3;
                        int n3;
                        Console.Write("Valor del Limite inferior en a:");
                        a3 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Valor del Limite superior en b:");
                        b3 = Convert.ToDouble(Console.ReadLine());
                        Console.WriteLine();
                        Console.Write("Ingrese N cantidad de numeros:");
                        n3 = Convert.ToInt32(Console.ReadLine());
                        Console.WriteLine();
                        h3 = (b3 - a3) / n3;
                        Console.WriteLine("El valor de h es:{0}", h3);
                        Console.WriteLine();
                        Console.Clear();
​
                        //Fila X
                        double x3 = 0;
                        double[] VectorX3 = new double[n3];
                        for (int i = 0; i < VectorX3.Length; i++)
                        {
​
                            x3 = x3 + h3;
                            VectorX3[i] = x3;
                        }
​
                        //Fila f(x)
                        double fx3;
                        double[] Vectorfx3 = new double[n3];
                        for (int i = 0; i < Vectorfx3.Length; i++)
                        {
                            fx3 = ((2 * VectorX3[i]) + 1) / (Math.Pow(VectorX3[i], 2) + VectorX3[i]);
                            Vectorfx3[i] = fx3;
                        }
​
                        //Fila 3(f(x))
                        double fxx3;
                        double[] Vectorfxx3 = new double[n3];
                        for (int i = 0; i < Vectorfxx3.Length; i++)
                        {
                            if (i == Vectorfxx3.Length - 1)
                            {
                                fxx3 = Vectorfx3[i];
                                Vectorfxx3[i] = fxx3;
                            }
                            else
                            {
                                fxx3 = 3 * Vectorfx3[i];
                                Vectorfxx3[i] = fxx3;
                            }
​
                        }
​
                        //Sumatoria  
                        double Σ3 = 0;
                        for (int i = 0; i < Vectorfxx3.Length; i++)
                        {
                            Σ3 = Σ3 + Vectorfxx3[i];
                        }
                       
​
​
                        double Resultado3;
                        Resultado3 = 3 * h3 * Σ3 / 8;
​
                        //Impresion Tabla
                        Console.WriteLine("|Lim inf={0}|Lim Sup={1}|N={2}|h={3}|",a3,b3,n3,h3);
                        Console.WriteLine();
                        Console.WriteLine("|  N |  X   | F(x)  | 2f(x) |");
                        double[] Tabla3 = new double[n3];
                        int c3 = 1;
                        for (int i = 0; i < Tabla3.Length; i++)
                        {
                            Console.WriteLine("| {0} | {1} | {2} | {3} |", c3.ToString("00"), VectorX3[i].ToString("0.00"), Vectorfx3[i].ToString("00.00"), Vectorfxx3[i].ToString("00.00"));
                            c3 = c3 + 1;
                        }
                        Console.WriteLine();
                        Console.WriteLine("|Sumatoria|=|{0}|", Σ3.ToString("00.000"));
​
                        Console.WriteLine("|Resultado|=|{0}|", Resultado3.ToString("00.00000"));
                        break;
                }
                Console.Clear();
            } while (accion != 0);
            Console.Clear();
            return;
        }
    }

View IL Code