On Fri, Sep 11, 2015 at 10:48:19PM +0200, aitor_czr wrote:
> A * (1/A) = 1 = (1/A) * A
>
> So, it must be square :-)
>

I will become pedantic now, but if A is a matrix, the interpretation
of the equations above depends on what "1" and "/" actually mean for
you. In general, 1/A does not mean anything when you deal with
matrices. The symbol "A^{-1}" is normally used to denote the inverse
of A. And the inverse is defined only for square matrices. Hence your
"conclusion" is actually a fundamental hypothesys to make those
equations mean anything at all :)

HND

KatolaZ

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[ Enzo Nicosia aka KatolaZ --- GLUG Catania -- Freaknet Medialab ]
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