Thursday, 30 July 2015

real analysis - Proof of Uniform Convergence of continuous functions




Suppose K is compact and fn is a sequence of continuous functions on K which converges pointwisely to a continuous function f(x), and fn(x)fn+1(x) for all x K and n N. Show fnf uniformly.





My thoughts:



To prove uniform convergence I think we should use the definition(epsilon delta). But I'm not sure how to use other conditions. I was trying to combine "uniform
continuous" and "pointwise convergence" but it didn't work.


Answer



Actually, this is the Dini’s Theorem. You can see this lecture note: http://www.math.ubc.ca/~feldman/m321/dini.pdf


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