$\vec{a}$

$\vec{b}$

O: (0, 0)
A = (2, 1)
B = (1, 3)
a = Vector(O, A)
b = Vector(O, B)
c: (a * b)
Text1: "\vec{a} \cdot \vec{b} =  \left( \begin{array}{c} " + (LaTeX[x(a)]) + " \\ " + (LaTeX[y(a)]) + " \end{array} \right) \cdot\left( \begin{array}{c} " + (LaTeX[x(b)]) + " \\ " + (LaTeX[y(b)]) + " \end{array} \right) = (" + (LaTeX[x(a)]) + ") \cdot (" + (LaTeX[x(b)]) + ")+ (" + (LaTeX[y(a)]) + ") \cdot (" + (LaTeX[y(b)]) + ") = " + (LaTeX[c]) + ""