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
660sec in 3 days.
So 220sec per days
220•5= 1100
1100sec = 18min and 30 second.
Ans:
18min and 30 sec
Answer:
100
Step-by-step explanation: