I believe the answer is D
<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:
Step-by-step explanation:
Use KCF method
Keep the first fraction
Change division to multiplication
Flip the second fraction.
÷ 
Answer:
24 mph for both 60 miles and 40 miles.
Step-by-step explanation:
We need to find how long it takes to get to college and from it.
Speed x time (x) = Distance (60)
30x = 60
x=2
It takes two hours to get to college
20x = 60
x = 3
It takes 3 hours to get back. It's a total of 5 hours, 2 hours at 30mph and 3 at 20. Now we need to find the average
30+30+20+20+20=120
120/5= 24
The average speed for the round trip is 24.
To do the second part, we follow the same process, but replace 60 with 40 for distance.
30x=40
x= 1.33
20x=40
x=2
We can add the total distance and divide by total time to find the average.
The total distance is 80. Time is 3.33
80/3.33=24
The average speed is still 24.
