You will probably get some help faster my learning to format code so someone can read it.
main()
{
float a,b,c,x1,x2,x,series;
double d;
printf("enter a,b,c and x1(pos) & x2(neg)");
scanf("%f%f%f%f%f", &a, &b, &c, &x1, &x2);
read:
x = (x1 + x2) / 2;
series = a * x *...