The system
A = [ 1 0 1 0 1 − 1 0 2 1 0 − 1 0 ] , b = [ 11 0 11 0 ] {\displaystyle A={\begin{bmatrix}1&0&1\\0&1&-1\\0&2&1\\0&-1&0\end{bmatrix}},\quad {\bf {b}}={\begin{bmatrix}11\\0\\11\\0\end{bmatrix}}}
is inconsistent. Find the least-squares solution of the system A x = b . {\displaystyle A{\bf {x}}={\bf {b}}.}
