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Limit problem - emergency

  1. Oct 6, 2004 #1

    k3n

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    limit problem - emergency !!

    Show that the converse is false

    LIM x-->c |f(x)|=|L|
    LIM x-->c f(x) = M != L

    email me !!
     
  2. jcsd
  3. Oct 6, 2004 #2

    Gokul43201

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    We don't do believe in doing others' homework for them. We will help, though.

    What ideas do you have ?
     
  4. Oct 6, 2004 #3

    k3n

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    uhm....right now i have no idea at all
     
  5. Oct 6, 2004 #4

    Gokul43201

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    What does |x| mean ?
     
  6. Oct 7, 2004 #5

    k3n

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    |f(x)| = the absolute value of f(x)
     
  7. Oct 7, 2004 #6

    HallsofIvy

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    You started by saying "show that the converse is false" but did say the converse of WHAT. I think you are trying to show that the converse of
    "if lim f(x)= L then lim |f(x)|= |L|" is false.

    The converse would be "if lim |f(x)|= |L|, then lim f(x)= L"

    You can show that a general statement is false by showing one example in which it is false.

    Gokul43201's question was not because he didn't know what | | meant. It was a hint that the difference between |L| and L is crucial!
     
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