#include <stdio.h>
#include<math.h>
#include<iostream.h>
float f(float x)
{return 14*x*x*x+4.3*x*x+1.06*x-0.173;}
float g(float x)
{return 42*x*x+8.6*x+1.06;}


void main()
{float x0,x1,e;
int k,n;
cin>>x0>>e>>n;
k=1;
do{
if(g(x0)==0)
{cout<<"g(x)=0\n";
break;
}
x1=x0-f(x0)/g(x0);
cout<<x1<<endl;
if(fabs(x1-x0)<e)
{cout<<"finally"<<x1;
break;
}
k++;
x0=x1;
}while(k<=n);

女生告訴我用牛頓法解的.....提供參考