/*tgs metnum no3.lagrange*/
#include<stdio.h>
#include<conio.h>
main()
{
int i,j;
float x[3],y[3],x0,sum,product;
clrscr();
x[0]=1;x[1]=4;x[2]=6;
y[0]=1.5709;y[1]=1.5727;y[2]=1.5751;
printf("\nmasukan nilai yang ingin dicari x : ");scanf("%f",&x0);
sum=0;
for(i=0;i<3;i++)
{
product = y[i];
for (j=0;j<3;j++)
if (i!=j)
product = product * (x0-x[j])/(x[i]-x[j]);
sum+=product;
}
printf("nilai f(%.2f) : %.6f",x0,sum);
getche();
return 0;
}