\[ \vec{a} \cdot \vec{b} \quad=\quad a_x b_x + a_y b_2 + a_z b_z + ... \] \[ \vec{a} \cdot \vec{b} \quad=\quad ||\vec{a}|| \cdot ||\vec{b}|| \cdot cos(\theta) \]

\[\vec{a} \times \vec{b} \quad=\quad (a_y b_z - a_z b_y, \quad a_z b_x - a_x b_z, \quad a_x b_y - a_y b_x) \]

\[ \theta \quad=\quad acos \Bigg( \frac{\vec{a} \cdot \vec{b}}{||a|| \cdot ||b||} \Bigg) \]

\[ s \quad=\quad ||a|| cos(\theta) = \vec{a} \cdot \hat{b} \]

\[ m \quad=\quad \sqrt{x^2 + y^2 + z^2 + ...} \]

\[ \hat{a} \quad=\quad \frac{\vec{a}}{m} \]

\[ \hat{a} \quad=\quad \frac{\vec{a}}{m} \]

\[ \begin{aligned} & \theta = \text{atan2}(x, y) \\[1em] & r=\sqrt{a^2 + b^2} \end{aligned} \]

\[ \begin{aligned} & ouais \end{aligned} \]