\( f''(0) = 1 \)
\( f''\!\left(\frac{2}{\pi}\right) = \frac{12 - \pi^2}{2\pi} \)
\( f''\!\left(\frac{2}{\pi}\right) = \frac{24 - \pi^2}{2\pi} \)
\( f''(0) = 0 \)