[OS X TeX] Latex symbol for "define equal"
Martin Berggren
martin.berggren at cs.umu.se
Tue Aug 21 07:59:18 EDT 2018
> On 21 Aug 2018, at 13:47, Markus Klyver <markusklyver at hotmail.com> wrote:
>
> The thing is that you can have several different definitions, all equivalent. Consider the definition "a matrix A \in \mathbb R^{n \times n} is invertiable iff A have a multiplicative inverse". It turns out that this is equivalent to a lot of things, among det(A) !=0, A having full rang, A having n linearindependent eigenvectors, Ax=0 only having the trivial solution, Ax=b having a solution (which is unique) for every right-hand-side b, etc.
I would save that this is a theorem, not a definition. I think of a definition as a “macro”; that is, giving a short name to a mathematical property. Example: a matrix A is called positive semidefinite when x^T Ax \geq 0 for all vectors x. The point is that you in each instances when the name is used, it can be replaced by its definition.
Sincerely,
Martin Berggren
-------------------------------------------------------------------
Department of Computing Science,
UMIT Research Lab
Umeå Universitet
Campustorget 5, S-901 87 Umeå, Sweden. Ph: +46-70-732 8111
http://www.cs.umu.se/~martinb <http://www.cs.umu.se/~martinb>, Martin.Berggren at cs.umu.se <mailto:Martin.Berggren at cs.umu.se>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://email.esm.psu.edu/pipermail/macosx-tex/attachments/20180821/e44e055c/attachment.html>
More information about the MacOSX-TeX
mailing list