f(t) a continuously differentiable function twice over the circle T1
cr its fourier coefficients and σn(f,t) partial sum of Fejer.
b. Consider k as -n≤k≤n , using cr coefficients calculate
c. Consider a function gn= max | f(t)-σn(f,t) | t in the circle T1
show that lim n*gn=0 n->∞
f is constant
The Attempt at a Solution
I end up with a +1.. the summation about f(t) is in relative numbers Z using fourier but here it is |r|>n is it from here that I can "delete" the +1 ?
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