1=2o 2/1=主 2,1=O 1=O, ˆ ] 0 ˆ [ , ˆ ] 0 ˆ [ [ ˆ , ˆ ] ˆ [ ˆ , ˆ ] 2 ˆ 0 2 2 0 0 = = =  =    + − j j j j j j j j j j    