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Defining matrice members as variables

ptc-5125091
1-Newbie

Defining matrice members as variables

So i kinda have the same problem in these 2 problems.

First one is:

Untitled2.png

In whiich i have to find the values of A and B members.

And the second one is:

Untitled3.png

In which 3 of the members have the value of 0, 3 of 1 , 2 of 2 and 1 of 3.

In both of those i am having trouble in defining the matrices and using those matrices to find solutions.

Any help is welcome.

5 REPLIES 5

Mathcad won't do it that easy out of the box, especially the second one, but it can help alot in solving the task. For example the second one:

matrixEqu2.png

As with the ideas for the second problem from Werner, Yon can use the symbolic engine to provide some help with understanding the matrix multiplication:

Capture.PNG

But in this case a solve block will produce an answer:

Capture.PNG

Note that I have included conditions for all the zero elements in the arrays.

If these are omitted the result could include non-zero elements here.

There are also 4 highlighted equations (currently disabled).

Your initial information has 10 unknowns, but the matrix equality only provides a maximum of 16 equations - so this is only 1 of many solutions.

Adding / changing these 4 equations or the initial guess values will give alternate answers to the problem.

Regards

Andy

You changed the definition of matrix B.

With the original definition we get a pretty integer result:

MatrEqu1.png

BTW, with your changed information you have 20 unknowns and only 16 equations.

The original task has 16 unknown and 16 equations.

My mistake - problem is, as always, not reading the information correctly.

Werner_E
24-Ruby IV
(To:Werner_E)

Here''s a solution for #1 without manual intervention and without the need to address the individual matrix elements.

MatEqu11.png

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