N19 | Maths Made Easy

N19

 

Question: Evaluate the expression below.

(9^{13}\div 9^5) \div 9^2

 

Solution: The laws of indices tell us that when you divide terms such as these, their powers are subtracted. So, dealing with the brackets first:

9^{13}\div 9^5=9^{13-5}=9^8

Therefore, bringing in the last term, the calculation becomes

9^8\div 9^2=9^{8-2}=9^6

Then, by whichever method you prefer, work out that

9^6=531,441