seconds.
Elapsed time is 0.081160 seconds.
Elapsed time is 0.082303 seconds.
</pre><h2>Underdetermined systems<a name="15"></a></h2>
         <p>The under-determined system A*x=b where A has more columns than rows has many solutions.  x=A\b finds a basic solution (some
            of the entries in x are zero).  pinv(A)*b finds a minimum 2-norm solution, but it's slow.  QR factorization will do the same
            if A has full rank.  That's what the factorize(A) and inverse(A) methods do.
         </p><pr