Answer: The multiplicative inverse of – 1 in the set {-1,1} is -1.
Step-by-step explanation:
In algebra, the multiplicative inverse of a number(x) is a number (say y) such that
[tex]x\times y=1[/tex] [product of a number and its inverse =1]
if x= -1, then
[tex]-1\times y=1\Rightarrow\ y=-1[/tex]
That means , the multiplicative inverse of -1 is -1 itself.
Hence, the multiplicative inverse of – 1 in the set {-1,1} is -1.