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Cross product through determinants and duality
The three-dimensional cross product can be reconstructed from two more general ideas: determinants and Euclidean duality.
For fixed vectors $\mathbf{u}$ and $\mathbf{v}$, the map
$$\mathbf{w}\mapsto \det(\mathbf{u},\mathbf{v},\mathbf{w})$$
is a linear functional of $\mathbf{w}$. Euclidean duality therefore associates it with a unique vector $\mathbf{p}$ such that
$$\mathbf{p}\cdot\mathbf{w}=\det(\mathbf{u},\mathbf{v},\mathbf{w})$$
for every $\mathbf{w}$. That vector is precisely
$$\mathbf{p}=\mathbf{u}\times\mathbf{v}$$
This explains at once why the cross product is perpendicular to both inputs, why its magnitude equals the oriented parallelogram area, and why swapping the inputs reverses its direction.