Answer:
The answer is the last one.
Step-by-step explanation:
Firstly, look at the first inequality and we get
, so
. In the second inequality, we have
, so
. Together, we know that the answer is the last one.
Answer:
8 or 9^8
Step-by-step explanation:
You have to add the exponents when they are being multiplied without parenthesis which means 3+5=8 so it's 9 to the 8th power.
Answer:1002
Step-by-step explanation:

and 
and

as 
Applying this we get
![\Rightarrow \sum_{1}^{1002}\left [ \cos^2\left ( \frac{k\pi }{2\cdot 2005}\right )+\cos^2\left ( \frac{(2005-k)\pi }{2\cdot 2005}\right )\right ]](https://tex.z-dn.net/?f=%5CRightarrow%20%5Csum_%7B1%7D%5E%7B1002%7D%5Cleft%20%5B%20%5Ccos%5E2%5Cleft%20%28%20%5Cfrac%7Bk%5Cpi%20%7D%7B2%5Ccdot%202005%7D%5Cright%20%29%2B%5Ccos%5E2%5Cleft%20%28%20%5Cfrac%7B%282005-k%29%5Cpi%20%7D%7B2%5Ccdot%202005%7D%5Cright%20%29%5Cright%20%5D)
every
there exist
such that 
therefore