$$ \newcommand{\i}{\mathbf{i}} \newcommand{\j}{\mathbf{j}} \newcommand{\cvec}[2]{\begin{pmatrix}#1\\#2\end{pmatrix}} \newcommand{\mat}[4]{\begin{bmatrix}#1 & #2\\#3 & #4\\ \end{bmatrix}} \newcommand{\scvec}[2]{\tiny{\cvec{#1}{#2}}} \newcommand{\smat}[4]{\tiny{\mat{#1}{#2}{#3}{#4}}} \newcommand{\nth}{n^{\text{th}}} $$ ...

$$ \newcommand{\i}{\mathbf{i}} \newcommand{\j}{\mathbf{j}} \newcommand{\cvec}[2]{\begin{pmatrix}#1\\#2\end{pmatrix}} \newcommand{\mat}[4]{\begin{bmatrix}#1 & #2\\#3 & #4\\ \end{bmatrix}} \newcommand{\scvec}[2]{\tiny{\cvec{#1}{#2}}} \newcommand{\smat}[4]{\tiny{\mat{#1}{#2}{#3}{#4}}} \newcommand{\nth}{n^{\text{th}}} $$ ...

$$ \newcommand{\xhat}{\vec{e_x}} \newcommand{\yhat}{\vec{e_y}} \newcommand{\rhat}{\vec{e_r}} \newcommand{\phihat}{\vec{e_\phi}} \newcommand{\r}{\vec{r}} \newcommand{\v}{\vec{v}} \newcommand{\p}{\vec{p}} \newcommand{\a}{\vec{a}} \newcommand{\F}{\vec{F}} \newcommand{\vector}[1]{\begin{bmatrix}#1\end{bmatrix}} $$ ...