Here's a few....
1. What is the additive inverse of 2/3 ? → -2/3
2. What is the multiplicative inverse of 2/3 ? → 3/2
3. Justify the statement, "Division is not commutative." → for example, 15/3 = 5 but 5/15 = 1/3
4. Is the set of whole numbers closed under subtraction? Justify your answer.
Whole numbers are 0,1,2,3,4.........
"Closed" in this case means that when we perform a certain operation with two set members, we get a third set member returned. The set of whole numbers is not closed under subtraction because, for example..... 0 - 4 = -4 and -4 is not a member of the set of whole numbers
7. What is the additive inverse of the expression -ab ? → ab .... because -ab + ab = 0
9. Is the set of non-zero integers closed under division? Justify your answer.
Definitely not.....example .......22/7 = 3 +1/7 and this is not a non-zero integer
10. Show the set of non-zero rational numbers is closed under division.
Let m = a/b and n = c/d such that a/b and c/d ≠ 0. Them m/n = a/b ÷ c/d = [ad] / [ bc] which is also a non-zero rational