Here , the identity element is NUMBER@1 , since NUMBER@1 × a = a × NUMBER@1 = a for any rational number a . The inverse of a is 1/a , since a × 1/a = NUMBER@1 .

When the number is NUMBER@1 , then the NUMBER@1 is not written because NUMBER@1 times any number is that number -LRB- NUMBER@1 × y = y -RRB- and so is not needed .
