Vypočítej:\( \cos \left[(\pi \cdot \pi)^{\sin \frac{\pi}{6}}-\frac{3 \pi}{4}\right] \)
\( \frac{1}{2} \)
\( 0 \)
\( -\frac{\sqrt{2}}{2} \)
\( \frac{\sqrt{2}}{2} \)