How many times is \( \int\limits_{\frac{\pi}6}^{\frac{\pi}3} \frac{\sin 2x}{\cos x}\,\mathrm{d}x \) bigger than \( \int\limits_{-\frac{\pi}3}^{-\frac{\pi}6} \frac{\sin 2x}{\sin x}\,\mathrm{d}x \)?
Let \( ABCDEF \) be a regular hexagon with the centre \( S \) and the side of length \( 3\,\mathrm{cm}\).
The point \( G \) is the midpoint of the segment \( AB \).
The vectors \( \vec{u} \), \( \vec{v} \), \( \vec{w} \), \( \vec{z} \) are indicated in the hexagon shown in the picture.
Find the dot product of: \( \vec{v}\cdot\vec{w} \), \( \vec{v}\cdot\vec{z} \) and \( \vec{v}\cdot\vec{u} \).