Two dimensional vector cross product formula a (x1, Y1), B (X2, Y2), then a × B = (x1y2-x2y1), right? It's absolutely right and can be proved. It's better to give comments and proof, and it's better to give the screenshot or prove it yourself

Two dimensional vector cross product formula a (x1, Y1), B (X2, Y2), then a × B = (x1y2-x2y1), right? It's absolutely right and can be proved. It's better to give comments and proof, and it's better to give the screenshot or prove it yourself

This is the determinant operation, is also the definition of cross product. Does not need to prove