Correct Option:Option B
Solution:The given expression is:

cos(3x) can be written as cos(2x +x). Expanding it, we get:

Using this value of cos(3x) in given equation, we get:
I’m 15 so the answer is number 1
Slope is calculated using:
slope = (change in y) / (change in x)
slope = (12 - 2) / (5 - 3)
slope = 10/2 = 5