Recent content by iamwanli

In Cooper's book, I can't think out the solution of the following exercise. Show that each creative set is contained in some simple set. By the way,they are not homework question. I read the book on my own and I am a beginner. Thanks for your hint.

Soppose that A,B are effectively inseparable,B is r.e,then how to prove that \bar{A} is productive