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Homework Help: Uniformly convergent sequence proof

  1. Feb 26, 2012 #1
    1. The problem statement, all variables and given/known data

    Let [tex]f_n(x)[/tex] be a sequence of functions that converges uniformly to f(x) on the interval [0, 1]. Show that the sequence [tex]e^{f_n(x)}[/tex] also converges uniformly to [tex]e^{f(x)}[/tex] on [0,1].

    2. Relevant equations

    The definition of uniform convergence.

    3. The attempt at a solution

    I tried to use the definition of uniform convergence to prove this, so I need to show that for all ε>0 there exists N≥1 for all n≥N for all x in [0,1] [tex]|e^{f_n(x)}-e^{f(x)}| < ε[/tex]. I tried to prove this from the fact that [tex]f_n(x)[/tex] converges uniformly to f(x) but I kept getting stuck and I'm not sure how to do this problem now. Can anyone help me please?
  2. jcsd
  3. Feb 27, 2012 #2


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    This seems like a promising first step:

    [tex]|e^{f_n(x)} - e^{f(x)}| = e^{f(x)} |e^{f_n(x)-f(x)} - 1|[/tex]
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