program: 3D Grapher
koordinatni sistem: Cartesian (Dekartov)
x(u,v) = (1+0.5*v*cos(u/2))*cos(u)
y(u,v) = (1+0.5*v*cos(u/2))*sin(u)
z(u,v) = 0.5*v*sin(u/2)
u [-10, 10] (40)
v [-10, 10] (40)