For which operations is the set {–1, 1} closed? choose all answers that are correct. a. addition b. subtraction c. multiplication d. division

A set is closed under an operation if performing the operation on the numbers in the set results in a number that is in the set.

Addition:

-2, 0, 2 aren't in the set, so the set isn't closed under addition.

Subtraction:

-2, 0, 2 aren't in the set, so the set isn't closed under subtraction.

Multiplication:

-1 and 1 are in the set, so the set is closed under multiplication.

Division:

-1 and 1 are in the set, so the set is closed under division.

The answers are C and D.

Ibelieve that c. recording would work best.