/*_tinh gan dung gia tri bthuc s=sqrt(2....*/

#include<stdio.h>

#include<conio.h>

#include<math.h>

int main()

{

    int n,i;

    float s;

    printf("nhap so nguyen n: ");scanf("%d",&n);

    s=sqrt(2*n);

    for(i=(n-1);i>0;i--)//chay tu n-1 ve 1

    s=sqrt(2*i+s);

    printf("s=%.3f",s);

    getch();

    return 0;

}

//dau tien la tinh can 2n, sau do tinh len can (2(n-1)+2n)