Econ 407: An Introduction to Matrices and Their Applications. In Economics tools from matrix algebra are used to solve systems of equations, to find soulutions for input-output models, in regression analysis and quantative systems that can be made linear through proper lineraization methods. If you want to use Maple, it is necessary to call the subroutine known as LINALG, as

illustrated below. The first example is a 3 by 3 matrix--it has three rows and three columns.

> with(linalg):
A:=linalg[matrix](3,3,[4,1,-5,-2,3,1,3,-1,4]);

> B:=matrix([[3,10,-5],[-6,3,1],[4,-1,4]]);

We can exchange rows and cols of a matrix by usingh

C:=transpose(A);

> with(linalg):

> evalm(A+C);

> AX:=evalm(A-C);

> evalm(A&*C);

> S:=diag(A);

>