.
Additive inverse of  is
 is  .
.
Multiplicative inverse of  is 2.
 is 2.
    In mathematics, the additive inverse of a number a is the number that, when added to a, yields zero.
    See this Wikipedia article  https://en.wikipedia.org/wiki/Additive_inverse
    A multiplicative inverse or reciprocal for a number x, denoted by 1/x or x−1, is a number 
    which when multiplied by x yields the multiplicative identity, 1.
    See this Wikipedia article  https://en.wikipedia.org/wiki/Multiplicative_inverse