Flash: Creating an Image Gallery in Flash

Not sure why someone has rated this 'terrible'.

this sucks

There seems to be a syntax error in Math.cos function on page 2 of the tutorial for the scrolling effect - can anyone help me figure it out?? Or offer insight into the "simpler command" he mentions in the second paragraph of the scrolling effect? I am a bit beyond my comfort level with the Math functions but need a scroll on rollover navigation for a deadline. Thanks!