Question

I NEED HELP PLEASE! THANKS :)

Answer 1

Answer:

$y = 2 \: cos \: (\frac{1}{3} x)$

option C is the right option.

Explanation:

General expression of a cosine function is:

y=A cos k X

where A is amplitude and 2 pi/k is its period.

In our case,

$- y = 2 \: cos \: (\frac{1}{3} x) \:$

has :

$amplitude = 2 \\ period = 2\pi \times 3 = 6\pi$

hence, the right answer is of option C

hope this helps...

Good luck on your assignment..

Answer 2

Answer:

The third option should be correct. Goodluck!