Are the odd numbers a closed set under addition? Justify your conclusion. Homework Help ✎
A set of numbers is closed under an operation if the operation cannot be used with numbers from the set to get a number not in the set.
Can you add odd numbers together to get a number that is not odd?
Odd numbers are not a closed set under addition. Some examples:
3 + 5 = 8 3 and 5 are odd, 8 is even
7 + 13 = 20 7 and 13 are odd, 20 is even
15 +15 = 30 15 is odd, 30 is even