Let \( \alpha , \beta \) be the roots of the equation \( x^{2}-\sqrt{2}\,x+2=0 \). Then \( \alpha^{14}+\beta^{14} \) is equal to:
\( -64\sqrt{2} \)
\( -64 \)
\( -128\sqrt{2} \)
\( -128 \)