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牛顿迭代法求方程根

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

float solution(float a, float b, float c, float d)
{
float x0, f, fd, h;
float x = 1.5;

do
{
x0 = x;
f = a * x0 * x0 * x0 + b * x0 * x0 + c * x0 + d;
fd = 3 * a * x0 * x0 + 2 * b * x0 + c;
h = f / fd;
x = x0 - h;
} while (fabs(x-x0) >= 1e-5);
return x;
}

int main()
{
float a, b, c, d;
float x;
printf("请输入方程的系数：");
scanf("%f %f %f %f", &a, &b, &c, &d);
x = solution(a, b, c, d);
printf("\n");
printf("所求方程的根为：x=%f\n", x);
return 0;
}