Ответ:
y' = e^{\(\operatorname{tg}\) \(\frac{x}{3}\)} \(\cdot\) \(\operatorname{tg} \frac{x}{3}\)'
y' = e^{\(\operatorname{tg}\) \(\frac{x}{3}\)} \(\cdot\) \(\frac{1}{\cos^2 \frac{x}{3}}\) \(\cdot\) \(\frac{x}{3}\)' = e^{\(\operatorname{tg}\) \(\frac{x}{3}\)} \(\cdot\) \(\frac{1}{\cos^2 \frac{x}{3}}\) \(\cdot\) \(\frac{1}{3}\) = \(\frac{e^{\operatorname{tg} \frac{x}{3}}}{3\cos^2 \frac{x}{3}}\)
