Linear Combination of 3 matrices.

How do you compute the linear combination of 3 (1x3) matrices.

Answer 1

[Walter Roberson]

There are an infinite number of linear combinations of matrices: you cannot compute them all.

Is it possible that the question you are dealing with has to do with finding the point that is at the intersection of linear combinations of three vectors?

[Walter Roberson]

Let the vectors be v1, v2, v3, and let the target matrix be b. Then

 A = [v1(:), v2(:), v3(:)];
 x = A\b

Then b is a linear combination of the vectors if and only if x either only has one column or else x(:,2:end)./x(:,1) is the same (to within round-off) for all entries in any given column. (But do be careful about dividing by 0)

Answer 2

[Porgs]

I'm trying to prove that one given matrix is the linear combination of 3 other matrices.