Equation Icon  ( a)2 2 2 2 3 guu = − 1 + raa Ω + r a − r S + O (r), (10.50 ) gur = − 1, (10.51 ) [ ] guA = r raa + 2r2Sa + O (r3) ΩaA, (10.52 ) [ 3 ] 2 1-2 a b 3 gAB = r ΩAB − 3r SabΩ AΩ B + O (r ) . (10.53 )