ex p = expand(pow(7*y*pow(x*z,2)-3*x*y*z+11*(x+1)*pow(y,2)+5*z+1,4)
*pow(3*x-7*y+2*z-3,5));
ex q = expand(pow(7*y*pow(x*z,2)-3*x*y*z+11*(x+1)*pow(y,2)+5*z+1,3)
ex p = expand(pow(7*y*pow(x*z,2)-3*x*y*z+11*(x+1)*pow(y,2)+5*z+1,4)
*pow(3*x-7*y+2*z-3,5));
ex q = expand(pow(7*y*pow(x*z,2)-3*x*y*z+11*(x+1)*pow(y,2)+5*z+1,3)