Newton's method for equations

newton.c

#include <stdio.h>
#include <math.h>

#define MAX 20

int main(void) {
    int i;
    double x0, x1, fx0, dfx0, eps = 0.0001;

    printf("x0 = ");
    scanf("%lf", &x0);

    for (i = 1; i <= MAX; i++) {
        fx0 = x0 * x0 - 2 * x0 - 1;
        dfx0 = 2 * x0 - 2;

        x1 = x0 - fx0 / dfx0;

        if (fabs(x1 - x0) < eps) {
            break;
        } else {
            x0 = x1;
        }

        printf("x%d = %lf\n", i, x1);
    }

    printf("x1 = %lf\n", x1);
    printf("f(x1) = %lf\n", x1 * x1 - 2 * x1 - 1);
    printf("i = %d\n", i);

    return 0;
}