Question

For which operations is the set {–1, 0, 1} closed?



Choose all answers that are correct.



A.


addition


B.


division


C.


multiplication


D.


subtraction

Answer 1

For addition:\[
1 + 1 = 2 \notin \{-1,0,1\}

\]

Answer 2

For division \[
1/0 \notin \{-1,0,1\}
\]

Answer 3

For subtraction: \[
-1 - 1 = -2\notin\{-1,0,1\}
\]

Answer 4

all three?