relationship of simple pendulum

hi guys,

I'm currently working on a physics report about a simple pendulum and cant figure out how to answer one of the questions:

3. "define all terms in the solution(x(t)=Acos(ωt)) and especially the relationship between angular frequency, and periodic time, T."

ive defined all the terms, A is amplitude, ω is angular frequency etc. but have no clue of the relationship between angular frequency, and periodic time?????

I know that ω=2∏/T = 2∏f

and

T=2∏√l/g

but don't get their relationship?

any help will be great.

cheers,
Joel C.