Whats happening in this cosine curve?

Question

I was given a formula: y = a cos k ( x-b) + c

I know that amplitude is a, period is 2pi/k, horizontal shift is b and vertical shift is c.

and i'm suppose to explain what is happening in the following: y = .25 cos (3x + 3pi/4 ) - 2

Thanks in advance

Answer 1

k=3

Period = 2pi/3

Vertical = -2

Horizontal shift is pi/4