Symbol and numerical value calculation

[prilu]

I have simple and for sure, for most of You silly question 😉

I have a matrix M, with symbolic values only

M=|a b|
|c d|

When I chose from symbolic toolbar determinent calculation command, I will recieve something like this"

|M|=|a b|-> ad-cb
|c d|

Now I wanna do exactly like this, but with numerical values.

|M1|=|1 2|-> 1*4-3*2 = -2
|3 4|

I wanna see how Mathcad exactly calculate this determinent, and I wanna see final value at the end of expression.

[ViktorKorobov]

a:=1 b:=2 c:=3 d:=4
a*d-b*c explicit,ALL->1*4-2*3=-2
Viktor

[ValeryOchkov]

Step-by-step:

http://twt.mpei.ac.ru/ochkov/Mathcad_14/Chapter1/1_018_All_Values_Step_by_Step.png

Val

http://twt.mpei.ac.ru/ochkov/v_ochkov.htm

[RichardJ]

There seems to be a bug in MC14 M030 in this respect.

Richard

[TomGutman]

In general Mathcad does not do a determinant by substituting in some expression for the determinant in terms of the matrix elements. For all but the most trivial matrices any such expression is much to big to be of any practical use. Rather it uses some form of Gauss-Jordan elimination, an iterative process.
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� � � � Tom Gutman