Can anyone help me start this out? I got absolutely no clue. Q: If A and B are n x n matrices, AB = -BA, and n is odd, show that either A or B has no inverse. I know that we have to show that either det A is 0 or det B is 0, but I have no clue how to show it with the given information. Q: If A^k = 0 for some k >= 1, show that A is not invertible. Again, same problem. Any help would be great, thanks.