Question

Neemo

Answer 1

Like a is an empty set that means it contains noo elements

Answer 2

yes !

Answer 3

but like ik that the empty set symbol is sometimes considered like an element

Answer 4

the empty set is a subset of all sets if I recall correctly

Answer 5

ya it is

Answer 6

like it can be a set that contains one element the empty set element

Answer 7

yes !

Answer 8

So ill give u the example here

Answer 9

kk !

Answer 10

Find the number os elements in the set

Answer 11

the empty set contains no elements, so it is not an element in itself

Answer 12

okkkkkk thanks

Answer 13

that is what i needed to know

Answer 14

welcome :)

Answer 15

It can be an element of another set ! for example A={∅}...the empty set is an element of A !

Answer 16

ohhh i seee

Answer 17

How many elements r in :
\( {x \in R : x^2 = -1} \)

Answer 18

I would say 0 elements

Answer 19

yeah !

Answer 20

that's it ( I guess no !) !:) !

Answer 21

lol Thanks :)

Answer 22

no ! I'm not talking about the medal ! I don't care about medals It's just a stupid button !

Answer 23

ikkkk lol

Answer 24

I meant anything else to ask ?

Answer 25

nope not yet lol

Answer 26

kk ! you can ask me anytime you want !
C u later ! :)

Answer 27

@Neemo can you site a reference? because my understanding is that the empty set is not an element because it has cardinality of 0

http://en.wikipedia.org/wiki/Empty_set

http://wiki.answers.com/Q/Is_an_empty_set_element_of_any_set_s


the empty set is a *subset* of any set, but not an element of any set as far as I know

Answer 28

kk I'll look for a reference ! But ... the empty set is also an element of the set of the subsets ......of any set !

Answer 29

I see what you are saying Neemo, but the technicality is a bit confusing. I admit I have not studied set theory deeply.

http://planetmath.org/FunctionsFromEmptySet.html

Answer 30

:) :) this is driving me crazy too ! set theory is not yet completed ! there are a lot of unfinished task there....
so ...this answer .
"The empty element is a subset of any set--the empty set is even a subset of itself. But it is not an element of every set; in particular, the empty set cannot be an element of itself because the empty set has no elements."
is correct ! he (or she) said that It sn't an element of every set ! "just " a subset !
is correct !
in wikipidia's article ! The power set of the empty set is a set containing only the empty set:
that's meam that the empty set is an element of "the power set"
a box that contain only empty box is not empty !
I hate when I say that :) :) ! Clear now !

Answer 31

Wow, still confusing, but a little more clear now.
I think this is where the Franko-Zermelo revision of set theory gets messy.
I guess it is still somewhat a work in progress as you say.
Thanks!

Answer 32

and I'm a "he" :)

Answer 33

you're welcome anytime ! I didn't mean you ! who wrote the answer in wiki answer ! Nice to meet you anyway :) !

Answer 34

likewise!