Question

C语言编程：牛顿迭代法求方程的根

2*x*x*x-4*x*x+3*x-6=0

Answer 1

1234567891011121314151617181920212223242526272829303132333435363738#include <stdio.h> #include <math.h>/******start******/double Resolve( double,double,double,double );/******end******/int main(){ double a,b,c,d=0; double y; printf("input a b c d:"); scanf("%lf%lf%lf%lf", &a, &b, &c, &d); y = Resolve(a,b,c,d); printf("output:\n%.4lf\n", y); return 0;}/******start******/double f(double a,double b,double c,double d,double x){ return a*x*x*x + b*x*x + c*x +d ;}double f1(double a,double b,double c,double x){ return 3*a*x*x + 2*b*x + c ;} double Resolve( double a,double b,double c,double d ){ double x0,x1,e; x0=1; e=f(a,b,c,d,x0); do { x1=x0-e/f1(a,b,c,x0) ; x0=x1; e=f(a,b,c,d,x0); }while( e >= 1e-5 ); return x1 ;}/******end******/