1. The problem statement, all variables and given/known data given: Vn+1=Vn*cos(pi/2^(n+2)) and Vn= pi/2 2. Relevant equations Write Vn in terms of n 3. The attempt at a solution how can i start this. I already know that -1<cosx<1 and i've already proved that this sequence is a negative sequence. Then our teacher said if its possible to write Vn in terms of n?