How to show that the Fourier's series of $f(x)=x$ uniformly converges?
After finding its coefficient, I got:
I showed the pointwise convergence.
- And I'm not even sure that's always negative. But I assume that it show its decreasing.
- And as far as $u_n$ is an alternated series
By Leibniz's rule $\sum u_n$ converges pointwise.
I want to study the uniform convergence, but I don't know how to manage it... can you give a method?