Matrix: finding x in A.x=b



On Nov 21, 2007 10:29 PM, Mansur Marvanov <nanorobocop at gmail.com> wrote:
> Is there any way to find vector x in A.x=b simply?
>
> I have:
> (%i105) A:matrix([1,2],[3,4])$
> (%i107) b:matrix([1],[2])$
>
> (%i115) solve(A.x=b,[x1,x2]);
> (%o115)                               []
> ^^^ Doesn't work:(
>
> How can I get vector x?
>
> There is function lsolve(A,b) in MathCAD. Is there the same in Maxima?

A possible way:

(%i1) A:matrix([1,2],[3,4])$

(%i2) b:matrix([1],[2])$

(%i3) invert(A).b;
                                     [ 0 ]
                                     [   ]
(%o3)                                [ 1 ]
                                     [ - ]
                                     [ 2 ]
(%i4)

Paul