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Homework Help: Need help on a Limit problem!

  1. Sep 21, 2011 #1
    lim x --> n ([[x]] + [[-x]]) where n is an integer and [[ ]] is the greatest-integer function.




    How would I go on about this?

    Would I have to plug in n for x? So i got ([[n]] + [[-n]])
     
    Last edited: Sep 21, 2011
  2. jcsd
  3. Sep 21, 2011 #2

    Mark44

    Staff: Mentor

    I think that your first steps would be to graph y = [[x]] and y = [[-x]], and then graph y = [[x]] + [[-x]].
     
  4. Sep 21, 2011 #3
    So this would be a step function? How would I graph this if there's no numbers involved?
     
  5. Sep 21, 2011 #4

    Mark44

    Staff: Mentor

    Yes, the greatest integer function is a step function. Do you know what the graph looks like? Do you know what the graph of y = [[-x]] looks like. Graph both, and then the graph of y = [[x]] + [[-x]].

    Why is it a problem "if there's no numbers involved"?
     
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