是否存在角\( a\cdot 3,\alpha \in (-\frac{\pi }{2},\frac{\pi }{2}),\beta \in (0,\pi \))\( ,\)使
\( \{\begin{array}{c}sin(3\pi -a)=\sqrt{2}cos(\frac{\pi }{2}-\beta ),\\ \sqrt{3}cos(-\alpha )=-\sqrt{2}cos(\pi +\beta )\end{array}\)同时成立?若存在\( ,\)求出角α\( ,\)β;若不存在\( ,\)请说明理由.