Answer:
The cosine function that is represented in the graph is:
Option B. f(x)=cos (x-pi/4)-1
Explanation:
The parent function is cos x.
cos x at x=0 has the maximum value 1.
The graph is shifted to the right (x-pi/4) with a maximum value 0 at x=pi/4, then the graph is shifted downward 1 unit.
Then f(x)=cos (x-pi/4)-1
Please, see the attached graph:
The blue line is the parent function y=cos x
The red line is the graph given