Question

If the fundamental period of the function f(x)=3cos(kx/2) is 2pi/3, then what is k?

Answer 1

The period of Cosine function is 2pi Now, the period of Cos (Ax) is 2pi/A

So the period of your function f(x) should be 2pi /(k/2), which is equal to 2pi/3

So, k/2 = 3

k = 6

Answer 2

thank you!! i got it!