Hello, If X and Y are closed sets Then prove that X + Y is an F-sigma set Note : X + Y = { k in R^n : k = x + y for x in X and y in Y} Thanks a ton!
Follow Math Help Forum on Facebook and Google+
Originally Posted by unit1 Hello, If X and Y are closed sets Then prove that X + Y is an F-sigma set Note : X + Y = { k in R^n : k = x + y for x in X and y in Y} Thanks a ton! Let { } be a dense subset of X (for example a set of points with rational co-ordinates) and { } be a dense subset of Y Then I claim that:
Last edited by southprkfan1; Apr 19th 2010 at 07:43 AM.
Hey thanks for that! I was wondering if it would also work with closed bounded subsets, as in compact subsets?
View Tag Cloud