What is the greatest value taken by the function f(x)=4-2cosx for x>=0 (1 Viewer)

[blacktown_]

this is a multiple choice q and the answer is either
2
4
6
8


please show working out for this question
thanks !!

 

[bedpotato]

y = 4 - 2 cosx
can also be written as:
y = -2cosx + 4
The amplitude is 2, and then add 4 = 6. So the greatest value is 6. The greatest value is the maximum y-value.

 

[blacktown_]

aww thanks!