5.1 Power with Negative Bases
Powers are covered in the section about natural numbers and you learn there that powers are repeated multiplication. Here is an example:
Calculating powers with a negative base isn’t difficult and an example could looke like this:
(-2)^{3} |
= |
(-2) **·** (-2) **·** (-2) |
= -8 |
A good method to show powers with negative numbers is to multiply two factors at a time:
(-2) **·** (-2) = 4
4 **·** (-2) = -8
Something very important to be aware of is when you are calculating with parenthesis. Look at this example:
(-3)^{2} |
= |
(-3) **·** (-3) |
= 9 |
-3^{2} |
= |
-(3^{2}) |
= -(3 **·** 3) = -(9) = -9 |
The conclusion is that you get different answers depending if the base is in parenthesis or not. |