define

My anwser: Yes as

a) if empty set = then A = which belongs to F

b) WLOG if A is finite let B = is uncoutnable but is fintire thus B belongs in F.

c) a union of finite sets is finite thus belong in F

- April 5th 2011, 08:02 AMrosh3000is the set F = {A|A or A^c is finite} over R a sigma algebra?
define

My anwser: Yes as

a) if empty set = then A = which belongs to F

b) WLOG if A is finite let B = is uncoutnable but is fintire thus B belongs in F.

c) a union of finite sets is finite thus belong in F - April 5th 2011, 08:11 AMPlato
- April 5th 2011, 08:36 AMrosh3000
Yes clearly finite,

No union is infinte and complement is uncountable infinte thus not in f

Thank you