Πράξη rangle

Αν

$\langle 3 \rangle =0$

και

$\langle π \rangle =π-3$

και

$\langle \dfrac{12}{5} \rangle = \dfrac{2}{5}$

τότε

$\langle x \rangle +\langle \dfrac{1}{x} \rangle =?$