Possibly stupid question:
I'm wondering if there is some trick for evaluating the continuity/differentiability of a Fourier series. In particular, I'm looking at the function $f(x)=\sum_{n=0}^\infty 2^{-n} e^{inx}$.
2026-04-28 18:03:53.1777399433
Continuity/Differentiability of Fourier Series
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Hint: Think about a relevant geometric series. Or about the M-test, or about comparison to a known series.