In article .com,
wrote:
why would "equations for getting the maximum use of a given width and
length of corrugated cardboard (roll) sheeting..." need to involve "i"?

Well, one is subtracting from a given area, and the numbers subtracted
are therefore 'negative'. As the numbers are _areas_, then we have a
negative number that often needs to have its square root taken.
Mathematically, this does not work. as -1 x -1 = 1. So. " i " is
introduced to make the calculations work.

Interesting application. Areas and lengths have different dimensions
(dimensional analysis), so you aren't talking about dimensionless values.
The width and length are also, presumably, orthogonal. I'm also not clear
what would involve you in such a calculation of an area of -1 x -1 that was
on the physical sheet...

Is there an advantage over just essentially representing the 'area' as a
vector result perpendicular to the surface and giving it a size of width x
length? (in effect, using a cross-product vector approach.)

Slainte,

Jim

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