Answer:
Make it as simple as possible, and use 1 and −1 .
1×1×1×1×1×−1×−1×−1×−1×−1=
15×(−1)2×(−1)2×−1=
1×1×1×−1=
−1.
So, the sign will be negative.
Another way of thinking about this is to not even think about the positive integers, as they won’t affect the sign. A positive integer times a positive integer is still a positive integer; a negative integer times a positive integer is still a negative integer.
So, you have five negative integers. Think of it like two negative integers, two more negative integers, and a single negative integer. Since two negative integers form a positive integer, you now have a positive, positive, and negative integer. This forms a negative sign.
