Źródło TeX:

\left|\frac{f^{(6)} (c)}{6!}x^6 \right| = \left|\frac{-\cos c}{6!}x^6 \right| = \frac{|\cos c|}{6!}|x|^6 \leq \frac{1}{6!}\left|x \right|^6 < \frac{1}{6!}\left(\frac{\pi}{3}\right)^6 \approx 0.0018