I haven't worked with this explicitly and I don't have much time right now, but I can get you started on understanding it.

what is the difference between 'n' and 'n-1' ? - food for thought.. even 'b/w 'n+1' ?

understand the definition of a dot-product.

understand that the cross product of 2 vectors gives you a perpendicular vector and how to do that math to find its value.

this calculation is not that complicated, the measurements seem to be the hardest part.

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