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Can you check to see if i did Arguments w/ quantified statements right? Tollens/Ponen

  1. Sep 19, 2006 #1
    Hello everyone! its me!

    I'm pretty sure I did these right but I need to make sure, the class average on the hws have been 70s, so i wonder what i got :bugeye:

    Some of the arguments in 7-18 are valid by universla modus ponens or universal modus tollens; others are invaldi and exhibit the converse or the inverse error State which are valid and which are invalid. Justify your answers.


    If a complication of a computer porgram produces error messages, then the program is not correct.

    Compliation of this program does not produce error messages.

    .:. This program is correct.

    I said P(x) = compliation of a computer program produces error messages
    Q(x) = the program is not correct.

    [tex]\forall[/tex], if P(x) then Q(x)
    .:. ~Q(x)

    invalid, inverse error.

    #17. If an infintie series converges, then its temrs go to 0.

    The terms of the infinite series n/(n+1) do not go to 0.

    .:. THe infine series n/(n+1) does not converge.

    So i wrote:

    [tex]\forall[/tex] x, if P(x) then Q(x)
    .:. ~P(x)

    Valid, Universal modus Tollens.

  2. jcsd
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