Establish the identity. cos 0 + cos (30) = - coto sin 0 - sin (30) Choose the correct sequence of steps to establish the identity. cos 0 + cos (30) - 2 sin (20) cos 0 O A. = - coto sin 0 - sin (30) 2 sin (20) sin 0 cos 0 + cos (30) - 2 cos 0 cos 0 O B. = - coto sin 0 - sin (30) 2 cos 0 sin 0 cos 0 + cos (30) - 2 sin 0 cos 0 sin 0 - sin (30) 2 sin 0 sin 0 = - coto