Guass迭代法

/*用牛顿迭代法求方程x*x*x-x-1=0的近似值，ε<=0.00001，牛顿法的初始值为1*/

#include<stdio.h>

#include<math.h>

double f(double x)
{
    return x*x*x-x-1;
}

double f1(double x)
{
    return 3*x*x-1;
}
int main()
{
    double x=1;
    double temp;
    int i=1;
    while(1)
    {
        temp=f(x)/f1(x);
        if(fabs(temp)<=0.00001)
            break;
        x=x-temp;
        printf("x[%d]=%lf\n",i++,x);
    }
    printf("得x=%lf   ",x);
    printf("ε=%.7lf",temp);

    return 0;
}