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Homework Help: Proving F is not an increasing function?

  1. Sep 6, 2012 #1
    1. (Initial Question) let f be a function from R to R. Without using words of negation, write the meaning of "f is not an increasing function."



    2. No Relevant Equations.



    3.(Attempt at Solution) Does this mean that I just need to rewrite the statement without using the word "not", or am I somehow supposed to prove that f is not an increasing function? If I am supposed to prove this, how would I go about that?

    Thanks!
     
  2. jcsd
  3. Sep 6, 2012 #2

    LCKurtz

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    Neither. You just need to fill in the blank spot in this:

    If f is a function from R to R such that ____________________________, then f is not an increasing function on R.

    You have a definition of increasing function to use to help you fill in the blank.
     
  4. Sep 7, 2012 #3

    HallsofIvy

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    There exist some x and y such that x< y but .... What will be true of f(x) and f(y) to show that f is NOT increasing?
     
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