1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: I can't figure out if this statement is true or false, i said false

  1. Sep 12, 2006 #1
    This chapter is working with negations of Quantified statements.

    True or False. All the occurrrences of the letter u in the title of this book are lower case. Justify your answer.

    I said false, because they arn't being clear when they say "this" If even 1 book doesn't have a lowercase its false. But what is the method you would go about solving this?

    I never took a negation of a non-if then statement. If its if then, its pretty easy:
    ~(Ax, if P(x) then Q(x)) equivlent too Ex such that P(x) and ~Q(x)

    Ax in D, Q(x) equivlent Ex in D such that ~Q(x)

    Note: A should be upside down, and E should be backwards.

    THanks! :biggrin:
  2. jcsd
  3. Sep 13, 2006 #2


    User Avatar
    Science Advisor

    If this problem was in a chapter of your textbook, look at the title of your textbook!
  4. Sep 13, 2006 #3
    It was, the title of my text book is:

    Susanna S. Epp
    Discrete Mathematics with applications Third Editition

    So is Susanna S. Epp part of the title? I think not, so it has to be false right?
  5. Sep 13, 2006 #4


    User Avatar
    Science Advisor

    Are all unicorns green? In logic this translates to,
    For all x, if x is a unicorn, x is green.
    or more informally
    If there is a unicorn, it is green.

    There aren't any unicorns, so the antecedent of that implication is false. So all unicorns are green.

    Does this help you?
  6. Sep 13, 2006 #5
    yes I believe so! Since the title of the book has no u's (they don't exist, like the unicorn), So All the occurrrences of the letter u in the title of this book are lower case.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook