<m>S(f)(t)=a_{0}+sum{n=1}{+infty}{a_{n} cos(n omega t)+b_{n} sin(n omega t)}</m>

<m 28>delim{|}{{1/N} sum{n=1}{N}{gamma(u_n)} - 1/{2 pi} int{0}{2 pi}{gamma(t) dt}}{|} ⇐ epsilon/3</m>

<m 20> int{x}{2}{dx} = {1}/{3}x^3 int{0}{1}{x^2 dx} = {1}/{3} </m>

<m 16> 3/{4 pi} sqrt{4.x^2 12} </m>

<m 16> lim{n right infty} sum{k=1}{infty}{ 1/{k^2}} = {pi^2}/{6}e^{i pi} + 1 =0 </m>

<latex>

  \frac{3}{4 \pi}   \sqrt{4 \cdot x^2   12}\\
  \lim_{n \to \infty}
  \sum_{k=1}^n \frac{1}{k^2} = \frac{\pi^2}{6}
  e^{i \pi} + 1 = 0 \\

</latex>