Thread: subtracting powers?
View Single Post
  #2  
Old July 2nd, 2009, 04:14 AM
yeongil yeongil is offline
Super Member
  
Join Date: May 2009
Posts: 532
Country:
Thanks: 37
Thanked 289 Times in 252 Posts
yeongil is a jewel in the roughyeongil is a jewel in the roughyeongil is a jewel in the roughyeongil is a jewel in the rough
Default
Quote:
Originally Posted by Sailee316 View Post
How do you subtract powers?

(i) 72 – 62
(ii) 92 – 82

Thanks
These are not powers. Do you mean
\text{(i)}\;7^2 - 6^2 and
\text{(ii)}\;9^2 - 8^2?

If so, then just evaluate the powers separately and then subtract:
\begin{aligned}7^2 - 6^2 &= 49 -36 \\&= 13\end{aligned}

I'll let you try the other one yourself.


01
Reply With Quote