Question

What is the frequency of `f(theta)= sin 5 t - cos 15 t`?

Answer 1

`(2pi)/5`

Explanation:

Period of sin (5t) ---> `(2pi)/5`
Period of cos (15t) ---> `(2pi)/15`
Period of f(t) --> least common multiple of (2pi)/5 and (2pi)/15.

`(2pi)/5` x (1) --->`(2pi)/5`
`(2pi)/15` x (3) ---> `(2pi)/5`
Period of f(t) --> `(2pi)/5`