 |
M.Azzi pose la question :
Hello,
(I) - In set theory can a given set contain both elements and subsets, as "elements", as in :
A = {1,2,{},3,{{3}},8}
If yes :
1 - then, is |A| = 6 ?
2 - if the empty set is a subset of every set,
2. 1. does {} = {{}}, {{{}}} etc? , and if the is true what are the respective cardinals of the latter three? (0,1,1?).
2 . 2. Why isn't {1} equal to {{},1}? and why should these two be equal without having the same cardinality?
Sorry if my questions are not well expressed.
Thank you for the great service you provide.
Harley Weston lui répond. |
