write a program to integrate a function using simpson 1/3 method in c++.

write a program to integrate a function using simpson 1/3 method in c++.

CODE:

#include<iostream.h>

#include<conio.h>

float f(float x){

return(1/(1+x));

}

void main(){

clrscr();

float a,b,h,sum1=0,sum2=0,sum=0;

int n;

cout<<"enter lower limit : ";

cin>>a;

cout<<"enter upper limit : ";

cin>>b;

cout<<"enter number of intervals : ";

cin>>n;

h=(b-a)/n;

sum=f(a)+f(b);

for(int i=1;i<=n-1;i++){

if((i%2)!=0){

sum1+=f(a+i*h);

}}

sum1=4*sum1;

for(i=2;i<=n-2;i++){

if((i%2)==0){

sum2+=f(a+i*h);

}

}

sum2=2*sum2;

sum=sum+sum1+sum2;

sum=(sum*h)/3;

cout<<"x\ty"<<endl;

for(i=0;i<=n;i++){

cout<<i<<"\t"<<f(a+i*h)<<endl;

}

cout<<"\n value of integral using simpson's 1/3 rule: "<<sum;

getch();

}

OUTPUT: