Question

Seja matriz A= (aij) 3x4 tal que  aij = | i+j, se i =j 
                                                          | 2i - 2j,i  ≠ j   

Answer 1

$\left[\begin{array}{cccc}a_{11}&a_{12}&a_{13}&a_{14}\\a_{21}&a_{22}&a_{23}&a_{24}\\a_{31}&a_{32}&a_{33}&a_{34}\end{array}\right]$

$\left[\begin{array}{cccc}1+1&2.1-2.1&2.1-2.3&2.1-2.4\\2.2-2.1&2+2&2.2-2.3&2.2-2.4\\2.3-2.1&2.3-2.1&3+3&2.3-2.4\end{array}\right]$

$\left[\begin{array}{cccc}2&-2&-4&-6\\2&4&-2&-4\\1&0&6&-2\end{array}\right]$