truth table help

LKS007

Well-known member
  • Jun 14, 2008
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    මාතර - මාලෙබ් - melbourne
    ඒ බන් මේකේ ඉන්වලිඩ් ද නැද්ද හොයාගන්නේ කොහොමද???



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    IDG

    Well-known member
  • Aug 3, 2012
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    වාහන ගොඩේ
    1) P V (Q -> R)=true 2) Q^~R =true

    take 1
    P V (Q -> R)=true
    But (Q -> R) = ¬Q V R
    so 1 is

    P V ¬Q V R
    Law of negation
    ¬¬(P V ¬Q V R)
    ¬(¬P ^ ¬¬Q ^ ¬R)
    ¬(¬P ^ Q ^ ¬R)
    from 2 Q^~R =true
    ¬(¬P ^ Q ^ ¬R)
    ¬(¬P ^ true)
    identity law (P ^true)=P
    ¬(¬P)
    P
     
    Jul 3, 2012
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    116
    0
    1) P V (Q -> R)=true 2) Q^~R =true

    take 1
    P V (Q -> R)=true
    But (Q -> R) = ¬Q V R
    so 1 is

    P V ¬Q V R
    Law of negation
    ¬¬(P V ¬Q V R)
    ¬(¬P ^ ¬¬Q ^ ¬R)
    ¬(¬P ^ Q ^ ¬R)
    from 2 Q^~R =true
    ¬(¬P ^ Q ^ ¬R)
    ¬(¬P ^ true)
    identity law (P ^true)=P
    ¬(¬P)
    P

    :):):)