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Math Help - Try these proofs involving sets

  1. #1
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    Post Try these proofs involving sets

    if A- B = A prove that A intersection B = null set.....
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  2. #2
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by instrument.santosh View Post
    if A- B = A prove that A intersection B = null set.....
    a proof by contrapositive, or a very similar one by contradiction will work nicely here.

    what can you come up with?
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  3. #3
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    hey how to do dat ...
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    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by instrument.santosh View Post
    hey how to do dat ...
    i'm assuming you're not very good at english which is why you type like that? if you do know better, please do not use chat speak

    what have you tried. let me see how you begin and we will take it from there. are you using the contrapostitive or a proof by contradiction? or something else?
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  5. #5
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    hey check this for the proof for the first one....
    let x belong to B
    =>x dosnt blong to A-B
    => x dosent belong to A
    => A intersection B = null set ....
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