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Homework Help: Logical Equivalencies

  1. Sep 12, 2010 #1
    kdYpm.png

    Everything in here makes sense up and till the last part, where they substituted (I think) F in for ~p ^ q, and then just ignored it and made it equivalent to the last part? Hope I'm not being too vague here.
     
  2. jcsd
  3. Sep 12, 2010 #2

    Dick

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    They observed that ((not p) and p) is always false (F). Then they used that (false or anything)=anything. Is it the 'F' that throwing you off?
     
  4. Sep 12, 2010 #3
    Oh ok I see so false and anything is always anything. That makes sense. So the F represents a substitution of the previous part but is also used to symbolize false, correct?
     
  5. Sep 12, 2010 #4

    Dick

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    F=false. Presumably they would write T=true. And (false and anything)=false, that's not what they used. (false or anything)=anything.
     
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