So, this is what it is, but then associativity of multiplication says that this is equal to this a bar inverse times a bar equal times b bar, but a bar inverse a times a bar is 1 bar times b bar is 0 bar, 1 bar times b bar is 1 b bar because 1 bar is the multiplicative identity.
కాబట్టి,* = , . * =0 = 0 ఎందుకంటే అనేది మల్టిప్లికేటివ్ ఐడెంటిటీ .