Option A

<em><u>Solution:</u></em>
Given that we have to rewrite with only sin x and cos x
Given is cos 3x

We know that,

Therefore,
---- eqn 1
We know that,


Substituting these values in eqn 1
-------- eqn 2
We know that,

Applying this in above eqn 2, we get



Therefore,

Option A is correct
Answer:
Frankie have 6 coins
Step-by-step explanation:
For every 5 coins Carmen gets ,she gives 2 to her brother Frankie
Out of 5 coins, Carmen given 2 to her brother Frankie
So Carmen has 3 coins and Frankie has 2 coins
Ratio of coins , Frankie to Carmen is
2: 3
We need to find the number of coins Frankie has if Carmen has 9 coins
ratio of Frankie to Carmen is x : 9
Now make a proportion and solve for x

Cross multiply it
2*9 = 3*x
18 = 3x
Now divide both sides by 3
so x= 6
Frankie have 6 coins
<h2>
Answer with explanation:</h2>
The number of letters in word "ALGORITHM" = 9
The number of combinations to select r things from n things is given by :-

Now, the number of combinations to select 6 letters from 9 letters will be :-

Thus , the number of ways can six of the letters of the word ALGORITHM=84
The number of ways to arrange n things in a row :
So, the number of ways can the letters of the word ALGORITHM be arranged in a be seated together in the row :-

If GOR comes together, then we consider it as one letter, then the total number of letters will be = 1+6=7
Number of ways to arrange 9 letters if "GOR" comes together :-

Thus, the number of ways to arrange 9 letters if "GOR" comes together=5040
The question didn't make sense, could you add more to it?
The answer too your question is 65 it is equal to the square root of 65