#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>
#define EPS 1e-15

//prototypes
double f(double);
void solve(double (*f)(double), double, double);
double root(double (*f)(double), double, double);
//----------

double f(double x) { return (x*x-9)*(x-1)*sin(x)/(x*x*x+2*x*x+9); }

int main(void)
{
    double l = -4, r = 4; //границы корней
    solve(f,l,r);
    return 0;
}

void solve(double (*f)(double x), double l, double r)
{
    const int n = 1e+8 + 3; int i;
    double h = (r-l)/n, x1 = l, x2;
    for  (i=0;i<n;i++)
    {
        x2 = l + i*h;
        if (f(x1)*f(x2)<0)
            printf("root = %.10f\n",root(f,x1,x2));
        x1 = x2;
    }
}

double root(double (*f)(double x), double a, double b)
{
    double c, fa = f(a), fb = f(b), fc;
    if (fabs(fa)<EPS)
        return a;
    if (fabs(fb)<EPS)
        return b;
    while (b-a>EPS)
    {
        c = (a+b)/2;
        fc = f(c);
        if (fa*fc < 0)
            b = c;
        else
            a = c;
    }
    return (a+b)/2;
}