Write-

(i) The set of numbers which do not have any additive identity

(ii) The rational number that does not have any reciprocal

(iii) The reciprocal of a negative rational number.

(i) Natural numbers

(ii) 0(zero) is the rational number which does not have a reciprocal.

(iii) Is a negative rational number

The reciprocal of a negative number must itself be a negative number so that the number and its reciprocal multiply to 1.

Example:-

Reciprocal