Need help in simplifying a trigonometric function

[TogoPogo]

Hi, I was wondering how to simplify this function that is inputted in Wolfram Alpha: http://www.wolframal...29%29%2Fn%29%29

I am trying to get from the inputted function to the 2sin[(x-y)pi/n] form. What steps do I take to get there?

EDIT: Nevermind, I got the answer. All I needed to do was use double angle formula lol

Edited April 21, 2012 by TogoPogo