To determine which number is an integer but does not belong to either subset of integers, we typically consider the subsets of positive integers and negative integers.
- Positive integers: 1, 2, 3, ...
- Negative integers: -1, -2, -3, ...
Now, let's examine the given numbers:
- −13: This is a negative integer.
- 0: This is neither positive nor negative; it's often considered neutral.
- 13: This is a positive integer.
Since 0 is an integer but does not fit into either the positive or negative integer subsets, the answer is 0.