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Set theory Watch

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    NM. Problem done.
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    {a} \subseteq P({a}) is false.

    Why is it false?
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    What's the definition of the powerset?

    Use that to write out the set P({a}). Then it's clear.
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    (Original post by Simplicity)
    What's the definition of the powerset?

    Use that to write out the set P({a}). Then it's clear.
    Thanks for your speedy reply. A power set is represented as 2^s, where, s, is the set of all the subsets......

    So the power set will be {a} and {}.....a is in the powerset, so I don't see why it's not true? I'm a pretty slow mate, so try to explain it a bit more for me, please.
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    (Original post by boromir9111)
    Thanks for your speedy reply. A power set is represented as 2^s, where, s, is the set of all the subsets......

    So the power set will be {a} and {}.....a is in the powerset, so I don't see why it's not true? I'm a pretty slow mate, so try to explain it a bit more for me, please.
    No,

    I see what you miss understand.

    {1,2,3} is a subset of {1,2,3,4}

    But, you are sort of saying {a} is a subset of {{},{a}}, which it isn't. It is an element through.
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    (Original post by Simplicity)
    No,

    I see what you miss understand.

    {1,2,3} is a subset of {1,2,3,4}

    But, you are sort of saying {a} is a subset of {{},{a}}, which it isn't. It is an element through.
    Oh. Because a is an element, that's why?
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    (Original post by boromir9111)
    Oh. Because a is an element, that's why?
    That's too vague.

    a is element of of {a}, but isn't an element of {{},{a}}.

    So not a subset by definition.

    Try to be more precise .
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    Ahh, yes. I was a bit vague but I know what I meant. Thanks mate for your help!
 
 
 
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