The mean is the average number meaning that it is all the numbers in a set added together and divided by how many number are in the set. In this case there are 4 numbers (16, 3, whatever number x is, and 5). So, to find out what x is, first you multiple 4 by the known mean which is 9.
4 x 9 = 36
Then you simply subtract 36 from all the known numbers to find x.
36 - 16 - 5 - 3 = 12
So x = 12
Let's check.
x = 5π/24
4x = 5π/6
cos 4x = cos(5π/6) = cos 150° = -√3/2
cos² 4x = (-√3/2)^2 = 3/4
4 cos² 4x -3 = 4 (3/4) - 3 = 0
Answer: TRUE
Answer:
x=0
Step-by-step explanation:
3+5(0)=3