Even powers of negative numbers:
Be very careful to distinguish between these problems. The placement of the parentheses makes a difference!

Base 
Exponent 
Evaluate 

3^{2} 
3 
2 
(3)(3) = 9 
( 3)^{2} 
 3 
2 
( 3)( 3) = 9 
 (3)^{2} 
3 
2 
 (3٠3) =  9

 3^{2} 
3 
2 
 (3٠3) =  9 
These will cause problems when you are evaluating expressions so be careful. If you are using a calculator, you must enter them correctly or the calculator will give you a wrong answer. Experiment with your calculator to be sure you can do it correctly.