<span>Hi! All you need to know is that cot stands for cotangent and its the reciprocal of tan i.e. cot(x) = 1/tan(x). You probably know that tan(pi/4) = 1 and that tan(3pi/4) = -1. Happily in these cases it means that cot and tan come out the same (1/1 = 1 and 1/-1 = -1).
-1 - (+1) = -2 and this divided by pi/2 = -2/(pi/2) which looks a bit untidy so multiply the top and bottom by 2 (to get rid of the 2 in pi/2) and the answer is -4/pi. HTH</span>
Answer with Step-by-step explanation:
We are given that A,B,C,D,E and F.
We have to find the number of different four -letter arrangements can be formed using given six letters a,if the first letter must be C and one of the other letters must be B and no letter can be used more than once in the arrangement.
Number of letters=6
We have to arrange four letter out of six
After fixing C and B then we choose only two letters out of remaining four letters and repetition is not allowed.
Permutation formula :
We have n=4 an r=2
Using this formula and substitute the values
Then, we get 

Hence, number of different four -letter arrangements can be formed using six letters when repetition is not allowed=12
Answer:
$1.66 per foot
Step-by-step explanation:
3 yards=9 ft
14.94/9=$1.66 per foot
Answer:
2q^6
Step-by-step explanation: