Got it now after plenty of sleep. 1
and {1}
imply {1}
Manx, you are a good friend because you put up with me.
[/quote
technically saying {1} E S is wrong. 1 E S given S {
1,{2}, {1,2}}.
{1} isnt an element of S. but i think i know where your confusion comes from. a subset gets
{} regardless so
{1
} represents the 1 in S.
{{2}
} represents the {2} in S and
{1,{2}
} represents the 1,{2} in S. on a test if you say {1} E S that would be wrong because there is no element {1} in S there IS an element of 1 in S. Saying that there is a
{1} E S means that this would be S {
{1},{2},{1,2}} saying 1 E S is saying there is a 1 in S which there is {
1,{2},{1,2}}