1. The problem statement, all variables and given/known data If C is a n by n matrix with complex coefficient show that there is an integer k >0 that depends only on n such that C, C^2,C^3,...C^k are lin dependant. 3. The attempt at a solution Its meant to be a full proof but the only idea I vaguely have is that i^4=i. I'm sure this is something standard to prove but I couldn't find it on google, so a link with an explanation would be appreciated.