Answer:
frequency = 1/(2π)
Step-by-step explanation:
The frequency of the function is found by comparing the argument of the cosine function to (2πfx), where f is the freuqency.
2πfx = x . . . . the argument of the cosine is x in f(x)=2cos(x) -4
2πf = 1 . . . . . . divide by x
f = 1/(2π) . . . . . the frequency of the function f(x)
