Question

Which equations show that the set of whole numbers is closed under addition?

Choose all answers that are correct.

A.
0 + (–1) = –1

B.
1 + 1 = 2

C.
2 + 0 = 2

D.
2 + (–1) = 1

Answer 1

im thinking c and a

Answer 2

The set of whole numbers is this set: {0, 1, 2, 3, 4, 5, ...}

Answer 3

basically nonnegative integers

Answer 4

Closure under addition means that you take two numbers from that set and add and you should get a number in that same set as a result.

Answer 5

ik but, can u give a ex. :)

Answer 6

for example,

the numbers 3 and 5 are in that set, add them

3+5 = 8

8 is also in that set as well

Answer 7

none of these equations show that the whole numbers are closed

Answer 8

ok.

Answer 9

2 of them hint at it I guess...

Answer 10

but to be closed you need to show it is true for ANY two numbers in the set, so it would take a very long time to do that if we were to check case by case.

Answer 11

I think they just mean particular examples. Not in general.

Answer 12

A more rigorous proof would be needed to prove it in general.

Answer 13

,yea

Answer 14

the more i think of it its prob. not c or a

Answer 15

could be idk.

Answer 16

well it's definitely not A

why not? because -1 is not part of the set that I wrote out above

Answer 17

ok so not a. could be c and d

Answer 18

yesssssssssssssssssssssssssssssssssssssssssss i got a 80%

Answer 19

we are not here to take a test for you.

Answer 20

ok srry

Answer 21

@zzr0ck3r that doesnt mean we cant help them with test

Answer 22

Just making sure the user knows

Answer 23

i dont know i just started here