Răspuns:
Explicație pas cu pas:
[tex]A(3)=\left[\begin{array}{ccc}1&3&6\\0&1&6\\0&0&1\end{array}\right][/tex]
[tex]A(5)=\left[\begin{array}{ccc}1&5&20\\0&1&10\\0&0&1\end{array}\right][/tex]
[tex]X=\left[\begin{array}{ccc}a&b&c\\d&e&f\\g&h&i\end{array}\right][/tex]
[tex]A(3)*X=\left[\begin{array}{ccc}a+3d+6g&b+3e+6h&c+3f+6i\\d+6g&e+6h&f+6i\\g&h&i\end{array}\right][/tex]
A(3)*X=A(5) => g=0 h=0 i=1
Iar de aici doar înlocuiești :)
