Page 2 of 2 FirstFirst 12
Results 16 to 18 of 18

Math Help - Set confusion

  1. #16
    Banned
    Joined
    Sep 2009
    Posts
    502
    This is a very basic set theory, and I can't even get it---it so sad.

    Dexel,
    Some by stander urged to me cross a street, and the other stop me before I got to the other side of it. Now, I am in the middle of it waiting for a disaster to happen.

    Quote Originally Posted by Drexel28 View Post
    I don't think what you are saying is correct. If a\in S THEN \{a\}\subseteq S. You seem to be having an awful lot of confusion. Have you tried looking at what subset means abstractly? E\subseteq S \text{ iff }x\in E\implies x\in S.
    To me  <br />
(E\subseteq S )\Longleftrightarrow(x\in E\implies x\in S)<br />
means

    (E=\{1\} and S=\{1,\{2\}, \{1,\{2\}\}\}) <br />
\Longleftrightarrow(E\subseteq S )

    or

    (E=\{1\} and S=\{1,2,3,4\}) <br />
\Longleftrightarrow(E\subseteq S )
    Follow Math Help Forum on Facebook and Google+

  2. #17
    Banned
    Joined
    Sep 2009
    Posts
    502
    Quote Originally Posted by Drexel28 View Post
    I don't think what you are saying is correct. If a\in S THEN \{a\}\subseteq S. You seem to be having an awful lot of confusion. Have you tried looking at what subset means abstractly? E\subseteq S \text{ iff }x\in E\implies x\in S.
    I see what you are pointing at. I found where I made mistake and marked it in red:

    (1\in \{1\} and {1}  \in S) \Rightarrow \{1\} \subset S was definitely sloppy.

    I meant to say (1\in \{1\} and 1 \in S) \Rightarrow \{1\} \subset S

    Thank you for watching over me.
    Follow Math Help Forum on Facebook and Google+

  3. #18
    Banned
    Joined
    Sep 2009
    Posts
    502
    [quote=canyiah;446827]
    Quote Originally Posted by novice View Post
    Got it now after plenty of sleep. 1 \in S and {1} \in S imply {1} \subset S

    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}}
    I see you are as confused as I was at the begining before I posted the question. This thread has been longer than I expected. I have just wriggled myself out exhausted. If you go back to where I began, you will see how I got out of it.

    Happy learning!
    Follow Math Help Forum on Facebook and Google+

Page 2 of 2 FirstFirst 12

Similar Math Help Forum Discussions

  1. DVs and IVs confusion
    Posted in the Statistics Forum
    Replies: 0
    Last Post: December 4th 2011, 03:09 AM
  2. Max and Min confusion
    Posted in the Differential Geometry Forum
    Replies: 9
    Last Post: May 18th 2011, 09:44 AM
  3. confusion?
    Posted in the Math Topics Forum
    Replies: 1
    Last Post: August 8th 2009, 11:03 AM
  4. a confusion
    Posted in the Advanced Statistics Forum
    Replies: 1
    Last Post: November 24th 2008, 02:59 AM
  5. Such confusion
    Posted in the Calculus Forum
    Replies: 5
    Last Post: December 3rd 2006, 09:05 PM

Search Tags


/mathhelpforum @mathhelpforum