Recent content by steven2006

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    Show Convergence of Sequence of Continuous Functions to an F-sigma Delta Set

    Let \{f_n\} be a sequence of continuous functions defined on \mathbb{R}. Show that the set of points where this sequence converges is an \mathcal{F_{\sigma\delta}}. Any help is appreciated.
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    How to Prove Sum of Binomials Equals 3^n

    StatusX, thanks. Sorry for the stupid question! Now i work it out.
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    How to Prove Sum of Binomials Equals 3^n

    Prove that \sum_{k=0}^n \binom nk 2^k = 3^n, \quad n \in \mathbb{Z}^{+} Can anyone help me? Thanks