I have the first one as not always true and the second and third as always true. I just wanted someone to check this because I think i'm doing them wrong.Quote:

Let A,B,C be sets.

(i)Which of the following are always true?

1). A \ ( B \ C) = ( A \ B) U C

2). A \ (B U C) = (A \ B) \ C

3). A \ (B <intersection> C)= (A \ B) U (A \ C)

Is there a difference between A \ B \ C and (A \ B) \ C?

Sorry I don't know how to get unions and intersections to work so I used a U for the union and wrote <intersection> for intersections.