B. congruent, im pretty sure
2cos^2 x = 1 + cos 2x
cos^2 x = 1/2(1 + cos 2x)
f(x) = 6cos^2 x - 4 sin 2x = 6(1/2(1 + cos 2x) - 4 sin 2x = 3 + 3cos 2x - 4sin 2x
Okay so to do the sqrt(75) you see if there are hidden squares. Split it to be the sqrt(25) and sqrt(3) then simplify. In the end, you get 5sqrt(3). Hope this helps!
Probability that you will get exactly 4 tails, if you flip a fair coin 7 times is: 
Step-by-step explanation:
We need to find the probability that you will get exactly 4 tails, if you flip a fair coin 7 times.
This is the combination question.
The total combinations will be: 2^7=128
Now, finding number of ways we can get exactly 4 tiles:
We will use the formula:

in our given question, n= 7, k= 4
Putting values:

So, Probability that you will get exactly 4 tails, if you flip a fair coin 7 times is: 
Keywords: Probability
Learn more about Probability at:
#learnwithBrainly
STEP - BY - STEP EXPLANATION
What to find?
The the value of secθ.
Given:
(4, 3)
⇒(x, y) = (4, 3)
Step 1
Draw a sketch.
Step 2
Substitute the values into the trig. ratio formula below.

From the sketch above, opposite = 3 and adjacent = 4

Step 3
Find the value of the hypotenuse side using Pythagoras theorem.
let h be the hypotenuse side.

Hence, hypotenuse = 5
Step 4
Substitute the values into the formula below:

But,

ANSWER
secθ= 5/4
tanθ=3/4