Answer:
y = 5 cos x
Explanation:
Start with
y = sin x or y = cos x.
Since f(0) is not zero, this is not sin x, so it is a modified y = cos x.
The period of the cosine function is 2π, and the graph shows a period of 2π, so there is no multiplier of x.
cos x has a maximum value of 1 and a minimum value of -1.
Here the maximum value is 5, and the minimum value is -5.
The amplitude has been multiplied by 5, so you need a factor of 5 multiplying cos x.
Answer: y = 5 cos x