Bai06: S(n)= 1/1*2 + 1/2*3 + ... + 1/(n*(n+1)).

// Bai06: S(n)= 1/1*2 + 1/2*3 + ... + 1/(n*(n+1)).

#include<stdio.h>
#include<conio.h>

void main()
{
	float S = 0 ;
	int i , n ;
	printf("nhap n : ");
	scanf("%d",&n);
	for ( i = 1 ; i <= n ; i++ )
		S += (float)1/(i*(i+1)) ;
	printf("tong la : %f",S);
	getch();
}