Metode Integrasi Numerik

Berikut adalah Kodingan dari Integrasi Numerik,,
akan lebih bagus jika ada tampilan outputnya,, namun untuk sementara ini saja dulu

#include <iostream.h>

#include <conio.h>

#include <stdlib.h>

#include <stdio.h>

#include <math.h>

float f(float xo)

{

float fx;

 fx=pow(xo,3)-(3*xo)+2;

 return fx;

}

int pil1()

{

  float btsa,btsb,h,fxo,fx1,fx2,fx3,n,i,sum,Deltafx;

  cout<<"Soal Latihan No. 1 \n";

  cout<<"===================================\n";

  cout<<"Input Nilai Batas Atas (b) : ";cin>>btsa;

  cout<<"Input Nilai Batas Bawah (a) : ";cin>>btsb;

  cout<<"Input Nilai n : ";cin>>n;cout<<endl;

  h=(btsa-btsb)/n;

  sum=f(btsb);

  for(i=1;i<n;i++)

     {

       sum=sum+2*(f(btsb+(i*h)));

     }

  fxo=(h*(sum+f(btsa)))/2;

  fx1=(pow(btsa,4)/4)-(3*(pow(btsa,2))/2)+(2*btsa);

  fx2=(pow(btsb,4)/4)-(3*(pow(btsb,2))/2)+(2*btsb);

  Deltafx=fx1-fx2;

  fx3=Deltafx-fxo;

  cout<<"1.Perhitungan Metode Numerik : "<<fxo<<"\n";

  cout<<"2.Perhitungan Metode Analitik : "<<Deltafx<<"\n";

  cout<<"3.Eror : "<<fabs(fx3);

  cout<<endl;

getch();

}

int pil2()

{

  float btsa,btsb,h,fxo,fx1,fx2,fx3,n,i,sum,Deltafx;

  cout<<"Soal Latihan No. 2 \n";

  cout<<"===================================\n";

  cout<<"Input Nilai Batas Atas (b) : ";cin>>btsa;

  cout<<"Input Nilai Batas Bawah (a) : ";cin>>btsb;

  cout<<"Input Nilai n : ";

  cin>>n;cout<<endl;

  h=(btsa-btsb)/n;

  sum=f(btsb);

  for(i=1;i<n;i++)

    {

      sum=sum+2*(f(btsb+(i*h)));

    }

  fxo=(h*(sum+f(btsa)))/2;

  fx1=(2.79487*btsa) + (0.312151*pow(btsa,2))/2;

  fx2=(2.79487*btsb) + (0.312151*pow(btsb,2))/2;

  Deltafx=fx1-fx2;

  fx3=Deltafx-fxo;

  printf("1.Perhitungan Metode Numerik : %.4f\n",fxo);

    //cout<<"1.Perhitungan Metode Numerik : "<<fxo<<"\n";

  printf("2.Perhitungan Metode Analitik : %.4f\n",Deltafx);

   // cout<<"2.Perhitungan Metode Analitik : "<<Deltafx<<"\n";

  printf("3. Error : %.4f",fabs(fx3));

   // cout<<"3.Eror : "<<fabs(fx3);

  cout<<endl;

getch();

}

int main()

{

  int angka;

  char huruf;

    awal:

    cout<<"MENU INTEGRASI NUMERIK (Modul Pert. 10) :\n";

    cout<<"METODE TRAPESIUM\n\n";

    cout<<"=============================================\n";

    cout<<"1. Soal No. 1\n";

    cout<<"2. Soal No. 2\n";

    cout<<"3. KELUAR\n";

    cout<<"Silahkan Input Pilihan Anda [1-3] : ";

    cin>>angka;

    if (angka==1)

      {

        pil1();cout<<"\n";

        goto awal;

      }

    else if (angka==2)

      {

        pil2();

        cout<<"\n";

        goto awal;

      }

    else {

       cout<<"Anda Yakin Akan Keluar Dari Program ? [Y/T] : ";

       cin>>huruf;cout<<endl;

       if (huruf=='Y' || huruf=='y')

          {

            cout<<"Semoga Bermanfaat dan Terima Kasih... (^_^)";

            exit(0);}

       else if (huruf=='T' || huruf=='t')

          {cout<<"\n";

           goto awal;}

    }

getch();

}