Thread: Uniform boundedness

Prove that the partial sums of cos nx are uniformly bounded. Note: Sorry I don't know laytex .

Attempt:

n/m, I've solved it.

Originally Posted by skepticsmind

Prove that the partial sums of cos nx are uniformly bounded. Note: Sorry I don't know laytex .

Attempt:

n/m, I've solved it.

Is this really unif. bounded? In which interval? If you work in then taking we get that so it can't be unif. (not even pointwise) bounded in the whole line.