niudundiedaifa.zip_切线

#include<stdio.h> #include<stdlib.h> #include<math.h> double f(double x) { double y; y=x*x*x-x-1; return y; } double _f(double x) { double y; y=3*x*x-1; return y; } void main() { double h;double x;int i; printf("please input x0\n"); scanf("%lf",&x); for(i=0;;i++) { printf("x(%d)=%6lf \n",i,x); h=(-1)*f(x)/_f(x); x=x+h; if(fabs(h)<.00001) { printf("the root of equation is %6lf\n",x); exit(0); } } }