Question

What is the period of `f(theta) = tan ( theta) - cos ( (2 theta)/9)`?

Answer 1

`18pi`.

Explanation:

The period of both`tan k theta and cos k theta` is `(2 pi)/k`

The separate periods of the two terms in f(x) are `2pi and 9pi`.

So, the compounded period for the sum is LCM of (2.9) X `pi= 18 pi`.