Negative numbers are a part of the real number system that can represent concepts such as debt, direction, and etc…
For every real number a, has a negative −a
a+(−a)=0
Examples:
- 77 - (−77)
- 12.6ˉ - (−12.6ˉ)
- 1.41421356237 - (−1.41421356237)
Properties of Negative
To works with negative numbers, we use following properties.
| Index | Property | Example |
|---|
| 1 | (−1)x=−x | (−1)5=−5 |
| 2 | −(−x)=x | −(−5)=5 |
| 3 | (−x)y=x(−y)=−(xy) | (−2)3=2(−3)=−(2∗3) |
| 4 | (−x)(−y)=xy | (−10)(−7)=10∗7 |
| 5 | −(x+y)=−x−y | −(9+7)=−9−7 |
| 6 | −(x−y)=y−x | −(3−5)=5−3 |
Law of Signs
Addition & Subtraction
(−)(−)=(−)(+)(+)=(+)(−)(+)=(−)(+)(−)=(+)
Multiplication & Division
(−)(−)=(+)(+)(+)=(+)(−)(+)=(−)(+)(−)=(−)
