float sumortpolsym(int n, float x, float c[], float a[])
{
	int k;
	float h,r,s;

	if (n == 0) return (a[0]);
	r=a[n];
	s=0.0;
	for (k=n-1; k>=1; k--) {
		h=r;
		r=a[k]+x*r+s;
		s = -c[k]*h;
	}
	return (a[0]+x*r+s);
}