[AMR] Fix error

electives/amr/parts/01_kinematics/06_wheeled-robot.tex

@@ -56,4 +56,4 @@ $\vec{b}_s = {\scriptsize \begin{bmatrix}
 
 \textit{Turning}: $\Omega = (\omega_l r_l) / R_l\! =\! (\omega_r r_r) / R_r$, $R\! =\! v / \Omega$, $\Delta \theta\! =\! \Omega \Delta t$
 
-\textbf{Discretized}: $\vec{x}_k = \vec{x}_{k - 1} b_i$ with $i \in \{s, t\}$, respectively
+\textbf{Discretized}: $\vec{x}_k = \vec{x}_{k - 1} + b_i$ with $i \in \{s, t\}$, respectively